Let's see if we be all shooting up this place or racing to the finish line.

If need be you can be more specfic.  Example JRPG or WRPG or MMORPG under RPG.

Anyhow, mine is Platforming.

But Turn Based Strategy and Adventure games come at a close second.

Females

Third/First person shooters and action adventure games.

At the moment racing games been playing a lot of Forza 4 and Forza Horizon.

I like a little bit of everything but my favorites tend to have excellent multiplayer or pocket monsters that has an infatuation with saying their own names. Narcissistic sons of bitches -_-

Jrpgs were my favorite genre growing up, ever since square and enix merged I just don't know anymore...

sandbox games seem to be my favorite but fps and strategy games are up there too

Sorry Poll added.

Platformer.
It just encompasses so many amazing games; Mario Galaxy 1 & 2, Donkey Kong Country 2, Donkey Kong Country Returns, Yoshi's Island, Mario World, Mario 64, Mario Bros 3, Kirby's Epic Yarn, Rayman Origins, Banjo Kazooie, Banjo Tooie...

No other genre has so many games that blow my mind.

Gotta go with RPGs, nothing even comes close imo.  The story in JRPGs is on another level, you get so much bang for your buck, and the gameplay in action RPGs like KH or Tales of is so fun.  You just have so much variety with RPGs.