Poll posted now , Took a while. I realize most games don't really fit any one genre anymore but try and pick the one it most resembles. GTA3+ is the hardest example to place. There is tons of shooting and driving yet I think really at the core it is an action-adventure with shooting and driving mechanics. Or clear Hybrids like the total war series.
also, for fun try and come up with as many sub genres as you can. I already listed a lot but there's more.
Real time tactics
Top Down shooters
and on and on and on.
Probably action RPGs of the Fallout / Mass Effect ilk. I like playing through as a good and bad guy, leveling up in different ways, etc. I particularly like Mass Effect's blend of action and RPG elements.
Also a big fan of Battlefield - huge coop games that really reward you for strategizing are a blast.
Past that, I like the little arcade-ish games. Limbo was fun, Defense Grid was worth three times more than I paid for it, many hours were spent playing Peggle, etc.
I was going back on forth between shooter and JRPG, but I ultimately decided to go with JRPG. It seems like I tend to enjoy almost all of those kind of games, even if they're rated as mediocre by reviewers or other gamers. I can't exactly say the same about the other genres.
MMO's are terrible now. I'm not sure how anyone who played a challenging game like EverQuest could ever seriously play WoW. It's so watered down in comparison.
But I guess a lot of people feel the same way with SC2.
Am I the only one that notices that Blizzards games, while of course good games and highly polished, are more or less simplified casual versions of their respective genres? I don't mind the RTS', and WC3 bucked the trend and was fairly complex, but as a lifelong RPG fan I've never liked their RPG's. Seems like the main focus is simplifying the process to be open to as large an audience as possible and perfect implementation of the Skinner's Box to keep them playing.
For my favourite Genre though it's:
1b. CRPG (I'm having a hard time seeing TES grouped with Diablo)