A version of Crysis 2 for the PC was recently leaked onto various torrent websites, and Crytek/EA are urging gamers not to download it, and instead, wait for the final version which will be released next month.
In a statement on the official website, Crytek said "Crytek and EA are deeply disappointed by the news [about the leak]. We encourage fans to support the game and the development team by waiting and purchasing the final, polished game on March 22."
Crysis 2 is due for release on the 22nd of March in the US and the 25th of March in the UK. It is due for release on PS3, Xbox 360 and PC.
Source: Crysis 2 Official Blog