Doritos Dash of Destruction has been released on the XBLA as a free download. I figured I'd mention this now since I don't know how long it will remain free for.
I got it - haven't tried it yet but the early reviews say that for free, it's not bad. Apparently, there's a free Toyota Yaris-themed game (called "Yaris") that was (is?) available on XBLA, but it's supposedly ridiculously bad, whereas the Doritos game is on par with a decent browser game.
In other news, Bomberman Live is currently on sale for 600 points (down from 800), and they've unlocked the Time Trial option in the Mirror's Edge demo.
(edited by KJames199 on 18.12.08 1144) JK: LJ, S&H, KMA, FB