What's weird is that I had a laptop that Vista actually ran well on, and I didn't have any real problems. Of course it was a higher-end laptop (similar specs and price to what Apple sold at the time).

It often feels like the biggest difference between Vista and 7 was actually time. As such, the cheap computers 7 shipped on were much better than the cheap underpowered computers Vista shipped on (despite both OSes likely having similar realistic requirements).

Win7 kinda was the SP2 of Vista more than a major version.