Alright everyone, here it is:
13" MacBook - i5 2.3GHz, HD 3000 graphics, 1280x800, no SSD (like the specs we're seeing)
13" MacBook Pro - i5 ~2.6Ghz, HD3000 graphics, 1440 by 900, 16GB SSD
15" MacBook Pro - i5 ~3Ghz, dedicated graphics, 16GB SSD Combo or 180GB SSD
17" MacBook Pro - i7 ~3.5Ghz, dedicated graphics, 32GB SSD Combo or 256GB SSD
The "Pro" will be used to deliniate the new SSD OS drive. That will be the marketing kicker, since it'll be seen as a very novel idea. We already know the plastic MacBook is going away, but that's mostly because plastic looks very dated. There will still be a computer in it's price range, but it will be a unibody, hence this 13" that we're seeing now. There will still be a 13" pro, and it will have SSD and high resolution display.
As for dedicated graphics in a 13"? Get real. Not going to happen. I think you'll be happy with the resolution and SSD in the end, but prepare for the reality that we're not going to see dedicated graphics in a 13". Not now, maybe not ever.