I tend to prefer games that can play in under an hour. I like to be able to lose one then win one in quick succession rather than spend all night/day losing one. As a result I play a lot of RftG and Dominion. Twilight Struggle and ASL are the two exceptions to this rule because the gameplay itself is so exhilarating that losing doesn't matter.
I have a bias towards card games, and prefer games with open-ended victory conditions and mechanics. Auctions annoy me as I'm no good at keeping tabs on relative values of in-game commodities, and artificial restrictions on number of turns or actions chafe (Agricola is a perfect example of games I can't stand due to artificial restrictions).
Apparently, given recent posting behaviour, one of my hobbies includes "antagonising wargamers on the internet". Not sure what that says about me.
I gave up on RPG in most ways around the time of D&D 3rd Ed. It just made me so depressed that roleplayers generally wanted lots and lots of grindy, crunchy combat and nothing else. The indie gaming revolution, or the burst of 21st century "story games", really reinspired me to come back to the fold.
I think, in GNS theoryspeak (which I don't necessarily like, but then, the descriptors work), I bounce between enjoying and being fulfilled by narrativist and simulationist play.
At this point my aim in being part of the RPGG community is to start as many conversations under game entries as possible, with a view to triggering more active communities here around the games I like. Content is essential!