Righteous, I'm using almost all of my 600GB HDD and that's even before I load my media library on. That's all games.
Most people don't have 100 games (Games are about 6gb).
You will need to wait a little bit for more sandy-bridge mobos to come out. Intel is the only one who has released them so far. If you wait about a month I'm sure alot more will be available. It's definitely worth it, though. The 1366 cheap has been out for something like 3 years.
That mobo isn't feature-rich either. If you are going to build a computer now it should have at least USB 3 support. Socket 1366 chips should use RAM in multiples of 3, not 2. So you can't really go with an 8gb kit.
Of course, that doesn't really matter because it would be stupid to buy an i7 now anyways.