As an early Christmas present, my wife acquired a MacBook Air for me. I'd been wanting one since they came out. I spent some time with both and decided to go with the $999 model as opposed to one with more ram or a bigger SSD.
I swung it open and loaded Sketchbook Pro 2010 using my iMac's optical drive. It worked like a charm and pretty soon I had my tablet drivers, Bean, Starcraft 1, and iWorks loaded on as well. I proceeded to open programs and as many windows as I could, a bit beyond what I would ever use at one time.
The tiny machine never stuttered, juggling as many as ten programs without any visible sluggishness. It switched between programs and loaded content as quickly as my MBP and in some cases more quickly. I could easily have Mail, iChat, Pages, and several windows in Safari open at once without suffering a hit to performance.
I decided to open up one of my book projects. My latest work is up to 101 pages, has graphics, and a great deal of formatting. It takes a couple of moments to open on my MacBook Pro, almost three "steamboats" of counting. It took about 1 and a half on my MacBook Air.
It'll piss you off when you realize how much of a bottleneck a standard hard drive is to the performance of a computer. My MacBook Pro should be twice as fast as my MacBook Air looking at their specifications. The SSD really does make that big of a difference.
Keyboard, trackpad, screen clarity and manufacture are all what you'd expect from Apple. The screen isn't covered in glass like a MacBook Pro, which I somewhat miss just for the protection it grants the screen. I thought the lack of a backlit keyboard would bug me, but I've been typing on that particular type of keyboard for 14 months. Light or dark, doesn't matter anymore.
I wouldn't recommend the 13.3 MBA to anyone unless they really need the SD Card Slot. The screen resolution and performance for the money isn't worth it having seen how well the $999 version performs first hand. The 11.6 defines portability because of how thin it is.
The only major drawback I've found is that the 11.6 MBA is like a half inch too wide to fit in most cases designed for an iPad or standard Netbook. There really aren't too many laptops out there that are the same size, thus not too many options for cases. Thank goodness for Waterfield Designs.