I've bought a new laptop from iBook/TiBook to PowerBook G4, to MacBook, to MacBook Pro to Unibody (15 & 17) to now a MacBook Air.
The unibody macs just rock. My fiance has my hand-me-down 2.6Ghz MacBook Pro (non unibody) and I think it's a flimsy computer that isn't built to be tossed around.
1. 17 & 15 have matte screens
2. 17 has ExpressCard 3/4
3. Faster CPUs
4. Newer CPUs
5. Faster Front Side Bus
6. Faster DDR3 ram at higher clock speed
7. Glass trackpad which is my favorite trackpad EVER on any mac
Finally, the best construction I've ever used or seen in a notebook. the 17" Macbook Pro Unibody runs circles around the original 17" MacBook Pro in both speed, reliability, performance and ruggedness.
we are all entitled to our opinions but I wouldn't take a free last gen macbook pro over the unibody models.