I entirely understand what your talking about. Being part of a tight community, like an active guild, is a fantastic experience. It doesn't just feel like an extra chat channel. When you can get a lot of members together it just feels like a party. Lots of good times.
I think that people play MMOs for the feeling of accomplishment for one thing. Gaining a level or getting that awesome chest armor you've been wanting, always feels like you accomplished something. I'm not a fan of games with no stats or leader boards or anything because those are were the time wasting begins. In an MMO, you can show off all that you've done with that time you invested and other living people will react to it. Games like TF2 and Counter-Strike are the pick-up-and-play games of the shooter world. You don't get anything, even virtual, for all the time you spend playing. There's no payoff except for the fun itself. If a game can manage to be fun AND give you some incentive to continue, why would it be a waste of time?
It isn't just a copy of GB. Even the most talented web designers can't generate a totally new layout for the whole site in that amount of time. Edit: Plus GB isn't an original layout. For those who remember, it's based strongly off of ComicVine