I just got my new DP867 with 768 RAM. I have to say that I am not that much impressed with speed, but as far as the whole OS X experience am syched! I really fell fresh after using Windows (since it looked like DOS), and Linux (early 90's, I remember f&*#% up my monitor trying to set up the X server) for over a decade. It feels like putting on those brand new briefs from grandma during christmas... AAAHHHH!
I tried WXP and went back to W2K. It was not worth it... Linux might be a great server platform, but as far as the desktop, it is a HACK, nothing but a HACK!
Anyway, that's my opinion so far...