The last part isn't true. I've got the bottom priced 11" and being an entrepreneur I use it heavily for design. My only issue is the memory. After CS5 and a couple other programs I was down to 10gb.I'm 80% in front of a big cinema display but even working on the go its great. Photoshop too. My usual is itunes, mail, 5-10 safari windows, Photoshop, Illustrator and no spinning wheel of death. My experience of Apple is nearly 10 years and came from a 15" MBP that died.
If you're questioning it, go for it...
Are you sure you do that all at once without slowing down on a MBA with 2GB RAM? I just tried my regular use case - Mail, Firefox, MS Word and Excel plus Adium and it was 350Mb into swap and switching apps wasn't all that instantaneous.
What does your swap usage show (Activity Monitor - page outs with all that workload?
However with 4GB it shouldn't be that much of an issue for this workload. So I might just bite the bullet given the Sandy Bridge and TB upgrades!
I have for the last 12 days, and this was after using an iMac from years back which processed everything excessively. Right now my swap usage is 640 MB. Worth mentioning, I am returning it tomorrow to get the latest offering. Probably in the same setup.
