do you have a need to buy the machine (besides learning purposes)…do you have a job(s) to cover a good chunk of the machine’s cost? if not, I’d hold off…everything I’ve ever bought without it being needed/paid for has been a bit of a waste in my mind…
but if you’re dead set on getting a machine now, either platform is great…windows, intel core 2 duos are smokin, wait till cs3 for the mac, and 4gb of memory should suffice (I have 4 in my machine, 3 for AE, 1 for everything else hehe)…