I had both, and I never let go of the MBA rev B except to run Windows on my MBP (one day per month). Once you use a MacBook Air with SSD, you will never go back.
However, when I owned my original MBA, I never let the MBP down for the MBA. It had a HDD, and it was not fun. It was more than just the HDD that was the problem with the original MBA though.
I would say get a MacBook Air dollar per dollar unless you need the dedicated graphics or something. The MBA is just plain fun as long as it's the high end model with SSD.
The display on both of my MBAs were extremely high quality just as the MBP (except have lower resolution than the MBP).