My personal pros and cons of DDO. Sorry if it's too long.
Pros
Combat
Combat is one of the biggest things that sets DDO apart from other MMO offerings, and is arguably the best thing about the game. It's fast paced action, has a very FPS feel to it (despite the lack of first person view which is coming with the next patch) and is twitch based. It is NOT auto attack plus hotkeys like WoW, EQ or LoTRO. Combat in DDO moves...you can't just start attacking a mob and then go make a sandwich. It's not a game that you can type chat with your guild and other various friends in the thick of a raid. But if you're an XBox live player coming from something like Call of Duty, you should feel comfortable with the controls...as a matter of fact, DDO can be configured to be played with an XBox controller plugged into your PC! Combat emphasizes collision detection, in other words, if your weapon model doesn't intersect the monster's body, you don't get a to-hit roll at all. Projectiles, including many spells, can be dodged and physical ones can be blocked with your shield. You have a button you can use to raise your shield and actively defend. You can tumble in combat. Enemies don't stand still and neither should you.
Voice Chat and LFM tool
Other titles have tools for the community that play those games to get together. You can turn on LFG flags and use various chat channels. DDO integrated voice chat early in it's life and never looked back. As a result, players from games like WoW might feel like there is no one playing the game and they are adventuring in a ghost town. There really isn't much type chat going on that I've seen. An occasional question gets answered, I try to say something when I notice it, but having voice be such an integral part of gameplay makes the chat window easy to forget. Besides, this game is all about the group, and group chat is typically lively, both voice and type (yes, some folks don't have or can't use microphones for one reason or another...they manage fine) Here we don't get groups by being LFG so much as we open up the social window to find groups that are LFM (looking for more) and if we're looking to do a specific quest, we start our own group advertisement on that LFM window. To any new player of DDO some of the best advice you can get is to make friends with the LFM tool as quickly as you can, learn to use it and you will be well rewarded with all the grouping you can desire. That's not to say there aren't slow days, but if you want a group, you can make it happen. Shrinking violets and shy guys get no sympathy.
Dungeons
Simply put, DDO offers some of the best dungeon crawling experiences of any title out there. All dungeons are instanced for each party, so the developers have a lot of freedom to make destructable environments, fiendish traps, multiple pathways and all manner of puzzles, tricks and fun. One of the early complaints was a lack of randomness which made dungeons quickly go stale from repetition, and while too much repetition can make anything grow boring, the DDO devs have done much to randomize things such as trap locations, rare monster spawns, chest locations and other elements that keeps things interesting these days. Whether its collapsing floors, monsters bursting out from behind exploding doors, the sudden schling of sharp blades thrusting out of walls or a portcullis dropping behind the group trapping them with several angry looking bad guys, DDO delivers on all fronts with rich action-RPG experience oozing from every pore.
Multiclassing
One of the downfalls, in my opinion, of games like EQ is that all characters of X class at Y level are basically identical. Sure, Bob the Wizard might have the Staff of Thingsgoboom while Steve the Wizard wields the mighty Scepter of Blowstuffup, but they pretty much have identical spellbooks, and you can invite either one into your group if you are looking to fill the arcane glass cannon DPS roll. In DDO no two characters need ever be the same. Make a pure cleric...do you want a battle cleric thats built to stand in the front lines with the other tanks, taking the punishment while dishing out the divine fury of your diety or would you like to be a more traditional healer cleric keeping your comrades standing and swinging to the last? Sure, WoW has talent trees and EQ has AA and many games of that style have a certain amount of customizability within the classes. But can you be a spellcasting rogue in WoW, blending all the arcane might of a wizard with trapfinding skills and melee damage from your sneak attacks? DDO's multiclassing system allows almost unprecidented freedom of character creation and customization.
Chests
A seemingly minor thing, but your loot is your own. Every person in the group gets his or her own pull out of the chest. There is no ninja looting, it's simply not possible. Theres no hogging all the loot by being fastest clicker or having a loot hotkey set up. Everyone gets their fair share and that's that. Any complaints about bad luck can be taken up with the RNG.
Cons
Small World
Everything in DDO is instanced, even the public areas. There are no vast tracts of land to get lost in, there is no exploring over the next hill to see whats beyond the horizon. This is a feature, though, not a fault. Fans of large, open worlds with miles and miles of virtual real estate will likely feel rather clostrophobic in DDO, but the big plus of this lack is that you don't spend half your available game time just getting to the location you want to play in. Getting logged in, in a group and into a dungeon, in other words, to start actually playing the game can literaly take only a matter of minutes. There are explorer areas that are just sort of outdoor quests, and they are walled in, but some of the areas and dungeons are quite large indeed, especially when you consider theres only a handful of other people in the zone with you, and you're not competing with anyone for spawns or drops. Somewhat related to this is a lack of mounts, but on this point you must understand, they are not needed in this game. Other games need horses and griffons and motorcycles because they have all this vast real estate. Get rid of the one and logic simply follows that there's no need to spend time coding the other. Paladins are sad pandas without their warhorses, though.
Learning Curve
Despite many recent changes and vast improvements, DDO is still a very difficult game for many people to learn. Twitch combat that has more to do with the speed of your fingers than the stats of your character, a deep multiclassing system and a host of character abilities, the possibility of perma-gimping your with a leveling up mistake, voice chat to get used to using, a community thats mostly in the elder game, and many other idiosyncrasies make DDO a little less forgiving to new players than many other MMOs. Turbine has done much to help here, however. The new Korthos Island intro area, hirelings (which can make soloing much more doable at the lower to middle levels), premade build paths, tons of new named low level gear and other features make getting into DDO much easier than it was three years ago. But the biggest stumbling block seems to be in the newbies themselves...if you come to DDO to play another WoW or EQ clone, you're not going to have much fun because DDO doesn't play like most other MMOs. It is very likely, unless you've played Dungeons and Dragons before DDO, that your first character won't be very good. Don't be afraid to delete and reroll, even if you've only made it through a couple of levels...the knowledge and experience gained will make your second (and third if needed) efforts all the better. Use the premade build paths. Though not uber, these premades are playable and have the leveling decisions made for you. Most players have a soft spot in their hearts for thier first characters, including me, but I can almost garuntee that most second and third characters are "better" (as in, less gimp)...and not just because of the favor reward unlockables.
Small Population
DDO is a niche game, there's no denying that. It is never going to have the multimillion sub counts of WoW. Unfortunately, many jaded gamers three years ago wrote DDO off because it didn't kill WoW. This attitude persists even now in some darker recesses of the gaming portion of the interwebs with any MMO released. As long as MMO success is only allowed to be judged against WoW, all MMOs will continue to be considered failures. DDO's community is pretty dedicated to the game and we do love it so...even if some of its flaws are teethgindingly frustrating. Most of us are thrilled to see newbies joining, and I'm here to let anyone interested in the game know, there is population, there are groups to be found, the PUG scene is alive and well on all servers and I hope I have convinced some of you to give it a try. The 10 day trial is free. Our population is global.
Grind
This is something that no MMO can ever really get away from, gamers are going to find grind in every corner of gamedom. We must all come to our own grind-equalibrium. Some MMOs have a mob grind...find a spot, camp mobs til your eyes bleed, repeat when you wake up and pry the "Y" key out of your forehead. Some have a raid grind for gear so you can be powerful enough for the next raid to get that gear so you can do the raid after. Some have the PvP grind or the crafting grind or whatever. DDO has quest grinding (and some would say reroll or alt grinding). Me, this is a grind I can tolerate because I'm not killing the same mob in the same location over and over, I'm not spending 14 hours poopsocking my way through the Plane of Lewtgrynder with 72 of my closest annonymous internet acquantances for two pieces of gear (one of which everyone in the raid has already), I'm not crafting 19,835 Stone widgets so I can start on Metal widgets, neither of which are actually useful for anything other than raising my crafting skill and bleeding my coinpurse dry. You can, if you like, run the same quest in DDO over and over...and I know plenty of veteran players who do just that with the high XP quests to rocket passed the low levels (which could be why many newbs see the same quests on the LFM all the time) as well as players ginding a particular chest in a quest for a certain item drop. Not to mention the "crafting" Turbine started implementing a couple mods ago which requires grinding certain quests for the ingredients. But it is entirely in the players hands to reduce this grind to a minimum and each raid (save one) has a three day lockout timer per character. I personally don't repeat quests very often on any given night, but the content is limited, so you will eventually run out of new quests to do...as long as I'm not running the same quest more than two or three times in a day, I don't feel like I'm grinding.
Content
Honestly, I feel anymore that this is really only a problem for the long time players. A new player starting today has a ton of content in front of them. Unfortunately, Turbine launched the game woefully short of quests and has never (and likely won't ever) recovered with their oldest players. Also, being that it's a niche game without the huge sub count, updates have gotten a bit further apart than they were at launch. This and advertisement are Turbines two greatest failings with DDO. My biggest ***** with the game is that it is uber-awesome with leetsauce and entirely too underfunded, underadvertised, and underrated.
DDO is a great game, and lots of fun...but it is what it is, and it isn't what it isn't. Turbine does a great job keeping DDO focused on what it does best, which is offering tight group play, dynamic and interactive quests, and fast-paced, furious, real-time combat action. More gamers need to appreciate DDO for what it is and does well, not what it doesn't do the same as some other game. DDO certainly deserves better than it got, from reviewers and critics, from Atari marketing, and most importantly from people giving it an honest, open-minded try.
Been playing the game since late alpha/early beta and I'll probably be playing til the lights go out. I hope to see many new players from the Escapist and I'm sure Sarlona will welcome you with open arms. I think there are some other servers too, but they're not important.