I'd like to pile on the the Forgotten Realms as well. The setting has its strong and weak points, and I am sure it could be a great place to adventure in the hands of a good DM. However, it has earned my ire above all others because players and prospective players in my campaign (not FR) will frequently approach me about using this or that feat or domain or spell from one of the FR books. I am of the generation that grew up with Greyhawk as the default setting, and those who grew up with FR as the default setting (which it still kinda is in terms of support) seem to think that anything in the setting is fair game for any campaign. Other setting I don't care for (Planescape, Dark Sun, Dragonlance) just sit there not bothering me, Forgotten Realms won't leave me alone.