Scrolling through my list of completed stuff this year. (Going off my list of games played would require too much effort)
Tried to pull out 10 that i enjoyed the most.
8. Shoot Many Robots - XBLA Jan 15 - Was a ton of fun to run this in (4 player)co-op. Highly recommended for a group setting.
15. Burnout Revenge - Retail Jan 31 - Absolutely love this series.
17. Ascend: Hand of Kul - XBLA Feb 12 - Technically died in beta on the 360. Still available on steam. Definitely suggest checking it out. Great hack n slash dungeon crawler RPGish style game. Hopefully Steam allowing updates has brought the game to its full potential.
34. Dungeon Defenders - XBLA April 1 - Dungeon Crawler-ish/Tower Defense-ish kinda game. Also highly recommended for 4 player fun.
36. World of Tanks - XBLA/GoD April 11 - Huge points for being a unique tactical shooter game. Gets a great deal of support in the way of new tanks/artillery for existing nations in addition to adding lines from new countries. I believe most recently French artillery was added to the huge plethora of vehicles available from USA, USSR, Britain, Germany, (can't remember if Xbox has China already or if that is only PC.)
38. Sacred Citadel - XBLA April 17 - More sidescrolling beat-em up/rpg-ish leveling style fun. 3 player cap made it reminiscent of Golden Axe.
42. Kinect Nat Geo TV - Kinect App June 13 - Fun interactive mini games AND great for kids. Highly recommended for households with children. Target age would probably be 12 and under depending on interests maybe older
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49. Crackdown - Retail July 6 - The last time i had played Crackdown was a week or 2 before street date. Excellent game wish i had played it sooner.
50. Charlie Murder - XBLA July 7 - Another fun 4 player co-op game. Beat-em up platformer. Unique art/story and complimenting music and atmosphere make for a great experience.
80. Guacamelee Super Turbo Championship Edition - XBLA Sept 20 - You know what this game is by now. Added bonus of a huge number of homages. Loved it.