Windows 7 was the turning point I remember, when Gates came back to make up for Vista and they took every piece of feedback possible.
Vista largely got criticised for:
- Higher memory usage (than XP).
- Driver issues (in particular graphics and sound). Because Microsoft made changes to the Windows Driver Model, and big name manufacturers (Nvidia, Creative, et al) weren't ready at release, and produced either buggy drivers, or no drivers at all.
The reason why Windows 7 was better received is:
- It wasn't called "Vista." It was/is fashionable to bash Vista. They could have literally re-released Vista without one change and it still would have been treated better than Vista was (which is essentially the 7 strategy).
- Hardware moved forward. Vista and 7 don't run well on 1 GB of RAM. By the time 7 shipped most new PCs had 2 GB or more.
- Drivers were fixed/improved. When 7 shipped it ran Vista compatible drivers which were time tested by that stage.
Ultimately I just roll my eyes at people who continue to be critical of Vista. At least 8/8.1 I understand their perspective (Start Screen, etc), but trying to bash Vista while holding up 7 as this incredible release is just strange given how similar the two are.
I'd say that Apple could have had a similar issue with going from OS9 to OSX, though they at least had a long period of some degree of backwards compatibility. They, however, handled the transition much better since they controlled all of the hardware and drivers.