They say there are two types of hard drive. Those which have failed and those which will fail!
Being paranoid, I back up my PS3 regularly to an old 500GB USB hard drive. The PS3 backup utility allows you to keep multiple backups from different dates on the external drive. I keep the last 4 or 5 backups, and delete the old ones when I think they are no longer of any use.
You might consider the simple solution of backing up the entire system as well as just backing up the game save data.
For my GT (and other) photos I have a much more extensive backup regime involving about 5 copies. Just in case.