Because of bugs and exploits that have cropped up in the Playstation 2 online title, SOCOM II, Sony is going to be releasing a patch to solve these problems. It does not require a hard drive, but it will take up space on your memory card. There is no word on how much space will exactly be taken up.
The word from Sony directly is: "At Sony Computer Entertainment America, we are continuing our commitment to providing an exceptional online gaming experience. The SOCOM II update is designed to remove any exploits that players may have found, and that by putting out this update, SOCOM II fans can continue to enjoy the best online console gaming experience. We will not be sharing a list of the changes that were made in this update to further prevent potential player exploits."
So the fact that they say it's only exploits and don't say what was being fixed is an attempt to lay the blame on the players and not the company, and also confirms the fact that there are bugs in the game. My problem with this is that console games shouldn't have bugs that need to be patched. Grand Theft Auto titles are notorious for having too many bugs, and that detracts from the gameplay, and it makes your company look bad because it shows that you're trying to rush the game. So please companies, get it right the first time.
Sony has promised real downloadable content once the PS2 Hard Drive is released, but until then, have an extra memory card handy in case this patch is huge!