The XBLA exclusive, open-world zombie killing fest, State of Decay, was downloaded more than 250,000 times in the first 48 hours. Undead Labs, developers of the game, touted the success on their blog. The game is the second fastest selling game on XBLA behind Minecraft.
I am currently playing through State of Decay for review and can already highly recommend it. It is only $20 and is easily the best zombie game on the market. Our review will be up next week to not get in the way of all of our E3 coverage this week.