I honest to god have no clue how anyone has derived any joy out of Fable 2. And I'd also pass up on Infinite Undiscovery, Lost Odyssy, and Blue Dragon. Those games bored the life out of me.

Best games for 360 that are RPG's would be Fallout 3 and New Vegas, as well as Eternal Sonata. The only good exclusive RPG I recall playing was Spectral Force 3. The VA's are terrible, and the dialogue is pretty badly translated, but on a whole the game-play itself is very well done.

For non RPG's though, Gears of War is one I don't think's been listed. THe first one was great, though I haven't played 2, though I don't see why it wouldn't be good.

And while I have not played it, Alan wake looks great. That's one of the big reasons I kind of wish I still had a 360.