Reports are popping up that the PC version of Battlefield 3 has been leaked on various torrent sites. Sources claim it's only the Russian version of Battlefield 3 that has been leaked. According to those who have attempted to download it, the installer and in-game languages are set to Russian.
About a month ago, leaked footage of Battlefield 3 on the Xbox 360 hit the web, and DICE. Unlike that footage, people have already experienced Battlefield 3 on the PC. Apparently, only the single-player portion of Battlefield 3 is playable, thanks to a "crack" that allows players to bypass Origin and Battlelog, which is requried on PC to play Battlefield 3. Of course, with most torrents, some are reporting virus and trojans bundled in the torrent.
With the game set to release in about a week, there's really no sense in risking the legal ramifications, or PC harm associated with the torrenting of the game. It appears the game was leaked by one of the Russian retailers who received an early copy of the game.
My advice is to just wait. We've waited this long for the official release of Battlefield 3; why not wait a week longer?