Crysis 2 on PC, Xbox 360's Gears Of War 3 and Super Mario Galaxy 2 on the Wii were the three most illegally downloaded games in 2011.
Crysis 2 was downloaded for PC 3,920,000 times, closely followed by Call Of Duty Modern Warfare 3 with 3,650,000, and Battlefield 3 with 3,510,000.
The numbers for Wii and Xbox 360 downloads were smaller, with just 1,280,000 for Super Mario Galaxy 2, which was also 2010's most pirated Wii game, and 890,000 for Gears Of War 3.
The figures, provided by TorrentFreak are gathered from a number of sources, and also showed that overall, illegal downloads for each platform are actually lower than in 2010.

http://www.gamesindustry.biz/article...s-most-pirated