Outside the games you'd already mentioned (I put some of these loosely according to genres that you like), I really enjoyed:

Action

• Bayonetta
• Batman: AA
• Shadow Complex
• Ninja Gaiden 2
• Castle Crashers
• Crackdown

Adventure

• The Secret of Monkey Island 1 and 2: SE
• Braid
• Assassin's Creed 2

RPG

• Mass Effect 1 and 2
• Fallout 3
• Dragon Age

JRPG

• If you like it more along the lines of Final Fantasy - Lost Odyssey
• Anime, action-JRPG - Tales of Vesperia
• Whimsical, fun, traditional - Blue Dragon

I'm sure there are more worth recommending than what I had and I'm sure people will fill the blanks.

Don't get Deadly Premotion or Too Human, not sure why people are suggesting those, maybe bitter you decided to trade in your PS3 for a 360?

No one mentioned LIMBO?! >:(

I haven't played it yet, gave the 360 to my bro and since then I only game on PC and PS3, but you should definetly check it out since everybody have been raving about it.

Lost Oddysey: Best JRPG this gen
Resident Evil 5: Not a great RE, but definitely an awesome game
GRiD: Awesome mix between arcade and sim racing
Mass Effect 1/2
Splinter Cell Double Agent/Conviction
The Orange Box
Alan Wake

I guess because Too Human is a really good game and Deadly Premonition is so bad it's actually good (and funny)

lol Seece.

"hush guys - hide the Xbox shame!"

Seriously, both too human and deadly premonition have their appeal and fun factor. I actually preffer them both to something bland like...Resident Evil 5.

*strikes 'ps3-sales!' off the xmas card list*

Buy Alan Wake. Then, realize that there are no more great exclusives in the system, and get your PS3 back. Unless, you love Halo, in which case, that's unfortunate.

I would recommend Deathsmiles...fun little game and pretty cheap. Plus, you get a faceplate if you get the limited edition!

I would have kept both consoles because both have some amazing libraries. Any you won't find an uncharted on the 360. Anyways the 1 game that is a must have for the xbox 360 is mass effect 2.Also preorder halo reach. If you are into jrpg i heard tales of vesperia and eternal sonata were very good.