the community game section of XBLA is a bit of a minefield in my experience, full of tat and with not a lot that's worth wasting the points at.
for me this is the first exception to that rule I've come across.
it basically plays like a simpler less frustrating version of Pixeljunk Eden, its incredibly polished with lovely art and 19 levels & a level editor for your 400pts (though sadly you can't swap levels with others).
you basically grab and spin your acrobat chap around brightly coloured levels collecting balloons and secret stars, the demo will give you the idea whether you like it or not, and as is the way each new level adds new obstacles and complexity.
control is nice and sharp as you grab and steer your chap in the air.
really nice simple little game and posting it up here as it deserves at least a butchers at from a few people, there are far worse and less polished titles up for 800 pts in the main XBLA area.
late edit
just realised this one a MS indie game prize thingy, can see why, here is a nice article from the dev team looking at what went right/wrong with the project