The way I look at it - I'm far more productive on my "old" Windows XP system (and my "ancient" AmigaOS system) than most people are who keep up to date with the latest OSes.
I'm editing video, doing 3d and 2d graphics, desktop publishing, animation, composing and recording music, using a graphics tablet, trans-coding video from DV to MP4, DIVX, MPEG2, CAD work, etc. etc. etc. etc. on my old machines.
Most people I know who have the latest and greatest Windows 7 computers are just checking e-mail, facebook, listening to MP3s and watching the occasional downloaded movie. They will probably only use a fraction of the computing power they have on their desk/laps. On the other hand I may have less CPU cycles available, but I use it to its full potential.
Heck, I could probably get more done with a well set up and tweaked Windows 98 machine than most people do with their new computers.
I don't play many games - and I don't need to play the latest cutting edge games that require powerful hardware or the latest version of Windows. If and when I do get the inclination to play - I have THOUSANDS of really great games made during the last 30 years (C64, Amiga and slightly older PC games) to fill up my time. It would take years to play them all. Heck, I haven't even finished all the amazing Infocom text adventures or the original Ultima series yet!