It happened last week with Halo 2, and now it has happened to Grand Theft Auto: San Andreas. The "it" is piracy, as Rockstar has confirmed that copies of San Andreas were stolen, and scans of the box and the instruction book have hit the internet. Unfortunately, that's not all that has been uploaded, as the entire game has been pirated, uploaded to the 'net and has no doubt been downloaded thousands of times already.
Needless to say, the authorities are pursuing the matter, and Rockstar has made it very clear that they are taking not only the physical theft of the game very seriously, but also warned that downloading the game is an equally serious offense.
If you have any information on and piracy related matters concerning the game, Piracy@RockstarGames.com is where you should direct your emails.