Yesterday morning, I was absolutely sick to death of the dreaded performance I was getting with Windows Vista Basic on an old Toshiba laptop, which has a 1.6 GHz Pentium M processor and 2GB of ram. So, I decided to install Windows 7 Professional on it, and WOW, just WOW.
The laptop is like an entirely new machine. Windows 7 Professional runs very smooth on it. During idle, it uses about 565 MB of ram. I have Office 2010 Technical Preview and Symantec Endpoint Protection 11.0.5 installed on it. What a difference the OS makes. Vista Basic used to crawl on this laptop, but now, the performance is very snappy. I couldn't be more happy with it. And to think, I was considering tossing this laptop out.
Windows 7 Professional is significantly better than Vista on low end machines.
Windows 7 scales very well. It booted up in 35 secs on an old 1.3GHz AMD Duron rig (Overclocked to 1.45GHz), 1Gb of PQI DDR 266, a 40Gb IDE HDD, and an ATI 9200 SE (No Vista drivers so no aero, games, etc). I think what you've stumbled upon is a combination of a solid OS and the lack of OEM crapware as mentioned above.