From IGN: http://www.ign.com/articles/2012/05/14/minecraft-on-360-sells-over-1000000
“After being out for less than a week, Minecraft: Xbox 360 Edition has sold over 1,000,000 units. Other impressive stats were also included in today’s press release, such as 5.2 million total hours of game time and 2.4 million hours of multiplayer.”