OK recently my girlfriend got a 11.6" MBA and i got a chance to use it for about a week. I was a very happy owner of a 13" MBP till the day i started using the Air. Now i cant go back to the 13". The main reason is the size/weight. I thought my 13" was very portable but it feels like a giant compared to the tiny Air. I think Apple should work really hard and innovate in the next generation of MBP to shave some weight and make it a bit thinner (even if it requires removing the optical drive) Another reason is the screen. Going from a 133 ppi to a 113 ppi screen makes a lot of difference. My MBP screen feels "pixelated" compared to the pixel dense 11.6. Another thing that i noticed was that the 16:9 screen works much better for what i do than a 16:10. Having another 86 vertical pixels does add to the experience. It made it easier for me to write a thesis on word while doing research on safari side by side. I wish Apple moves to 1600:900 in the next gen MBP. The MBA performed the same if not faster in the tasks i do everyday. Opening applications was snappier and the system felt snappier overall. I think Apple takes some cues from the MBA in the next revision of the MBP.