Note - This post is part of the 30 Day D&D Challenge.
Day 4 - Favorite Gameworld
This one's a bit tough. I've played in several worlds, but in most of them the world itself didn't have a lot of effect on gameplay. But having read a few of the D&D novels, I'm going to have to go with Greyhawk. There's no specific reason why; I just enjoyed the universe presented in those books. My second choice would have to be Forgotten Realms, but only because I'm most familiar with it.