Thanks to gtagaming
for the heads up on this one.
It seems the PC version of San Andreas will be shipped out on a DVD-ROM disc as opposed to a normal CDROM, this is somewhat expected though due to the immense size of the game. Take 2 haven't officially announced this but we can see from box shots uploaded on the US
Take 2 websites that it clearly shows it as being "PC DVD-ROM" format.
We'll have to wait for an official announcement before we know any more information.