I picked up World of Keflings, and Costume Quest from the XBLA sale(s) going on right now. There are some one day deals (April 1st) to check out tomorrow, including a couple add-ons (for Fallout New Vegas, and Fable 3) as well as a couple discounted games.
So far I've only put some time into WoK which is kinda like a avatar based RTS lite. You use your avatar and have control of the little Keflings helping them build buildings, giving them jobs, and more. A very "Sim" like game. I was happy when I got the first achievement...
Best Achievement Ever! I'm enjoying it, and on sale at 400MS points ($5) it's really neat. I would also recommend getting Dorito's Crash Course which is free (it was one of the finalist in last years Doritos promotion) another avatar based game that plays like the Wipeout tv show.
I went to the Source Code sneak last night at the Warren. I enjoy most time travel/alternate reality movie settings so I was intrigued by the previews. The simple premise is they can send someone into the body of someone else 8 minutes before they died. There was a terrorist attack on a commuter train which they believe is a "warm-up" for something much bigger, so Colter Stevens (Jake Gyllenhaal) is being sent back to find out who the terrorist is (think Groundhog Day with a little Quantum Leap). I really liked it, it wasn't until afterwords that some of the time logic seemed questionable, but overall a fun action ride.