I like my games as follows
-Rythem Games- (examples: Elite beat agents, Guitar Hero, Rock Band, or DDR) These are good for killing hours and sometimes burning calories. Many rythem games have more then 1 difficulty and can keep a whole party playing.
-Fps- (examples: TF2, CS:S, RE) Fps's are good for solo and online play. Many have varied gameplay modes and various additional content that can be unlocked after a 2nd play through.
-MMORPG- (examples: Fable, WoW, Monster Hunter) These require the most time and patience for the gameplay to payoff. Developers continually add too their games, which creates a sorta Player Vortex. The only down fall is a subscription fee.
-Puzzle- (example: Portal, Picross) Provides single player goodness with an online community to share puzzles/levels across.
If it's not obvious, I don't own an Xbox or a Ps3. I have my 3 trusty systems, DS, Wii, and of course, my PC.