I'm still on XP because there is no clear choice for an upgrade path. I have a pile of business, programming, and electrical engineering applications that work well on XP and maybe fine on Windows 7. I don't like the bloat, interface, and locked-down nature of Win7. But do I wait for Win8? Or maybe try some Linux flavour and run XP/7/8 in a VM? It's really not an easy choice. Larger enterprises must hate this.
Have you actually seriously tried Windows 7? I couldn't stand Vista, but Win7 is a worthy successor to XP. It's faster, more memory efficient, and more stable. I've done my fair share of tweaking to make it more XP-like but many of changes are improvements.
Most businesses I work with are now moving to Windows 7 after skipping Vista entirely.
At my old job, I was initially running xp on a thinkpad with 2GB of ram and I never had any issues with performance. I was doing standard web development work and used a relatively lightweight editor.
I switched over to win7 on the same laptop and they gave me 4GB or ram. Using the same software, the system lagged so much I had to go back and upgrade to 6GB of ram just to get the PC running at the xp-level of performance.
Something was broken on your setup. I run Win7 on extremely resource-constrained computers (1GB RAM, Pentium III 1GHz) and it works considerably better than XP SP2. I've had the same experience on old-but-not-ancient (Pentium M 1.7GHz, 2GB RAM) machines as well as screamingly fast new boxes (3.4GHz quad-core i7 with 16GB RAM). Across the board, Windows 7 beats out XP SP2 in perceived performance, and I'd be willing to bet it does so in real performance too but I can't be bothered to benchmark.
That's entirely possible, I never bothered to look at the junk IT installed on it. I also used the base Aero interface, which I suspected was a resource hog. I never tried to optimize performance since memory was free.
I also haven't ran XP with less than 2gb of ram since 2005, so I don't know what kind of slowdown xp experiences under resource constraints.
But my perceived performance equilibrium was about 2gb with xp to 6gb with win7.
It sounds like your machine probably wasn't capable of running Aero on whatever IGP it had, more than anything. Aero Basic runs excellently on even really old stuff (and handles screen drawing much more intelligently than XP did, so it feels considerably snappier).
6GB sounds excessive for that situation, but if your IGP is getting testy about system memory, it seems likely that it'd require a hell of a lot to simulate decent behavior.
(Typed on my Toshiba Win7 netbook, with a 1.6GHz Atom, 1GB of RAM, and Aero running without a hitch.)
There are a lot of usability improvements as well. Maintaining the "All Programs" menu in XP was a full time charm. In 7 you just press start (or hit the Windows key) and type the first couple of letters of the program you want and hit enter.
Vista is what drove me to Mac OS, Windows 7 does not seem like much of an improvement in my limited testing. I hated the fact that Microsoft would just move everything around for no good reason, so I had to relearn to do everything I could do in XP. I managed with Dos v3.3 -> XP.