I've been waiting for this since before christmas. My MacBook Air isn't really up for the task of photo editing, but I loved it's portability. I'm willing to go with a bigger laptop for more performance, and the screen will be killer. Mine should arrive in a few weeks, and I'm looking forward to the performance and screen size boost. I'm always on the go, and it weighs only albs, so it should be easy enough to lug around with me.
It is definitely expensive, but is also the perfect computer for what I needed, powerful portable and a good screen. I probably would wait a while if I had a better current computer (11.6 MBA, 1.6Ghz core 2 duo, 4G ram), or maybe buy a used 15" one. Right now is a great time to buy a used 15" MB pro off of Craigslist or kijiji.
T3i / Tokina 11-16 2.8 / Tamron 17-50 2.8 / Sony Nex-5 / 40mm f/2.8 Pancake / 50mm 1.8 II /100mm f/2.0 / 580 EX II, 2x430 EX II's