Yeah, well I highly suspect this entire thread is just flame bait....but what the hell I'll bite anyway.
I can't comment on endgame, as I only played to around 45ish on my main character and played various others to 30 or so, but I can give an impression of my experiences to date.
As other people have said, it all depends on you. I'm not a huge fan of WoW personally, as firstly I think it's a stupid idea to split your entire playerbase in half and make each half unable to interact with the other half in any manner that doesn't involve blades, spells and other varieties of maiming eachother.
The PvP IS horribly unbalanced. It was that way every time I tried PvP through-out my time playing and from the opinions i've seen and read (and friends I know who play), that doesn't change at later levels. If you are a big PvP fan, then I'd highly recommend Guild Wars if you still want some MMORPG goodness, or otherwise pick up a game like League of Legends (it's free!), or just about any other PvP orientated game, if the levelling/exploring aspect means nothing to you.
You will get frequently ganked by people who are dozens of levels higher than you, but luckily for you have nothing better to do for the next three hours but sit on your corpse and kill you again every time you try to flee. Granted there are non-pvp servers that somewhat solve this problem.
I found the community aspect to be terrible personally. I've played several MMO's and WoW is the only one I've had zero success finding someone likeable in, who wasn't already an existing real life friend. I tried multiple guilds - all full of annoying children who only just learnt to swear and found it the most entertaining thing ever, or adults pretending to be said children so they can act like morons. I think the most conversation I got out of anyone random (ignoring gold sellers and beggers) was "kek" from people corpse-camping me.
Anyway, the game is bright, colourful and so mindnumbingly simple that just about anyone can play it to a fair degree of success with ease. The only part that really requires any skill is PvP and that most often comes down to Level->Gear->Class in that order, thus removing the need for skill.
As a first MMO, i'd probably highly recommend it, just because it's easy and gives you a flavour of what they are about. But there are much better ones out there. I'd consider giving Lord Of The Rings Online a go, as at some point over the next month or two it is becoming free to play, and is pretty much the same as WoW, but with a better storyline, better playerbase (in my opinion), and slightly more involved gameplay mechanics.
Anyway, that's just my opinion.
Elivercury.