250GB HDD on a console? Why? I certainly don't need that, I store all my movies, TV shows and music on my PC. Its a cool prospect and its fun that they're kicking up some dust but I don't think anyone besides the most hardcore PS3 and/or Sony fans will bite and swallow that one.
I would hardly consider myself hardcore, but I'm close to running out of space on my 160GB PS3 just from game installs, PSN games, and a couple hi-def movies.