Barozi on 11 March 2013
Not exactly XBLA, but interesting nontheless regarding digital sales: Xbox Live had a huge Games on Demand sales during the end of February and the beginning of March and we can see their impact on TrueAchievements.org:
http://www.trueachievements.com/n12494/ta-gaming-stats--feb-25th-to-march-3rd-2013.htm
Remember there are only 200.000 registered users on TrueAchievements.
