On processor/ram: I've had both configs... 1. N280/2G, and a N270/1G which i set up for friend. I have to say I notice no speed or responsiveness/snappiness diff between the two. The mem issue is probably due to the fact that OSX is just really good at managing swap. The proc issue makes sense if you think about it... 1.66 vs. 1.6 is just not enough of a diff to human perception. The only time I noticed a little diff was when I load up lots of apps... i.e. in addition to Safari: Chrome, iTunes, iPhoto, and playing Farmville (flash!)
on the wireless card, after reading some problem reports for the 1510 (not many, just a few), I decided to just not waste time on it, and went with the G which *no* one has problems.
So, if I were doing it over, I'd spend the $ on the color I want, save 20-25 bucks with the N270, and go with 2G, and the g card.