I still do play World of warcraft and enjoy it a lot. I'm generally not a fan of levelling games, but having spent so many years hoping that
UO would actually have something to it again rather than just being a chat room with avatars, it does make a welcome change. I hear a lot of complaints about
WoW that say there's little endgame content, yet I've been happily playing the game since it was released and curiously I've found endless things to do at level 60 *shrugs* I still haven't done everything I want to in the game, so I'm not sure what gives them that impression *chuckles*
I do agree though that whatever reasons made you stop playing before will still be there when you come back. Its the same with any game really. Think carefully about why you stopped playing the first time, it could save you money.
Once something about that game no longer holds your interest enough to get you to log in or want to pay the subscription fee, no shiney new expansion is going to make things any better.
The expansion is indeed out on January 16th (allegedly) and there are two versions, the standard and the collectors edition. No idea on price, but then these things tend to vary dependant on where you buy them anyway.
Feel free to PM me if you have more specific questions and I'll do my best to answer things for you.