Really depends on your consumption. If you anticipate downloading a lot of demos, downloading a lot of High Definition videos, installing a lot of games, utilize those games that allow you to capture gameplay footage, etc... Then yeah, go for the 250. The PS3 is my least played system, and I have a launch model 60 GB, and it took me just under a year to fill it up. I have a 120GB 360 Elite, also filled that up recently. On a separate matter, i have about 3 terabytes of 'stuff' plugged into my PC right now.

So it depends. I think you will be okay with the 120, though. You don't have to keep everything, particularly game installs for games you don't play anymore, or demos for games you already own.