I just got a base model 13" air and was thinking about going with 8gb but as it was special order from Apple and I had a bunch of gift cards from best buy I decided against it. I do a lot of parallels work on my computer (nothing taxing just an office management software always open on an external display). Tested it out today, gave 1gb of ram and 2 cores to parallels which worked just fine, then opened IE and chrome in parallels, plus safari, chrome, garageband, iPhoto, photoshop CS4, word, and excel to get to the point where the ram was paging out constantly. I noticed basically no slow down by doing this, mission control was still smooth, the verge in safari was as smooth as it ever is, basically everything worked just as if I did not have that much open. Not sure if it is the faster SSD helping or what but even though I would feel better having 8gb just in case it seems as though 4gb will work just fine for the average user even if they are using a virtual machine