An 11" MBA with 256 GB SSD (or anything larger than 128 GB) and 4 GB of RAM.
If the higher capacity drive isn't available in the next Sandy Bridge update, I'm going to be really disappointed.
And while I say I "want" this, it's something I'm going to buy when it comes out. I may even sell my 15" i5 2.4 GHz MBP because I wouldn't mind an 11" MBA as my primary laptop at the moment.