Cut my teeth on the spectrum and BBC then Atari ST, and have since used almost every iteration of windows from 3.0 (plus lots of DOS) onwards (3.1, 3.11, 95a + b, 98 + osr2, ME, 2000, Nt3.5 (briefly), NT4 (ditto), XP plus some vista and a sniff of 7), plus a smattering of older MacOSes (7~9) and more OSX than I can reasonably take, and a few different flavours of Linux and Unix (Solaris etc) alongside tasting some more esoteric arrangements.
I'll have Win7 (whichever flavour is equivalent to XP Pro/TabPC) straight up the middle on my next computer, thanks. It's easily the least bolshie and most intuitive out of the current offering, at least as far as I'm concerned. OSX damn near drove me out of my mind with its outright user-hostile wierdness in some places and worse reliability. Well, OK, that's unfair. Equal or maybe even imperceptably better reliability, but far less robust against everyday errors. EG, a scratched CD drives it insane... it's far from perfect. It is, basically, a very shiny appeal-to-newbies wrapper around an unremarkable Unix-ish shell. I daresay NeXTStep would probably have been a better choice for the latterday Macs.
Win7, I suspect, will still probably allow me to drop back to a disgustingly plain "Windows Classic" theme such as I use on XP, should I so desire, and drop away into the background of both my perception and the PC's computational resources, being the well oiled set of only-as-flashy-as-necessary cogs that keep the actual programs turning well up top, looking after files and connections, and glueing everything neatly together.