What do you want in an MMORPG?
What's fun do you? Do you want PvE? Do you want PvP? Odds are you only found WoW fun because of the community that was good for a while and then started to die down. Do you have friends that want to try things with you? That's a big factor.
Guild Wars is a much much different type of "MMO" in the fact that it relies on heavy instancing and most areas are instanced for you and your party, meaning that you'll only be with people who were in your party in town when you leave to enter an area. It has NPC bots with surprisingly decent AI who will follow you around and attack your target/attack things that you tell them to, if you want them to join you (makes it easier to level as a pure healing class, say, if you wanted to.) You can get two classes. One primary job and one secondary job. There's not really item crafting, though. You can get NPCs to make you things if you bring them the right items, but it's nothing like having a profession.
Interesting but maybe not what you're looking for. However, free to play, so that might mean something to you.
What are your tastes in theme? Fantasy? Sci-Fi? KOTOR is supposed to be really good once it's out. Could try an EVE trial out if you want.