Put a 1TB HDD in my PS3 fat today. Took all of five minutes and all of 30 to update the OS and do a backup restore of my saves, games, etc. I wish I'd known it was going to be that easy I'd have done it years ago.
I did a full system backup rather than just backing up my saves. When I uploaded it all my games and apps were there. Google ifixit for PS3 and at the bottom the second article link explains the system restore. It was surprisingly easy.