Paul Thurrott posted part 6 of his Windows 7 review
When Microsoft unleashed Windows Vista on a surprisingly unsuspecting world three years ago, the software giant delivered on its promise of a major, revolutionary Windows release. But the downsides to such sweeping changes are many, and in the case of Windows Vista, these downsides outweighed the benefits, thanks to narrow-minded and forgetful tech reviewers, screechy Apple advertising, and other factors. And none of those downsides weighed more heavily on users, perhaps, than performance. When it first shipped, Windows Vista simply ran more slowly than its predecessor on the same hardware. You know, just like virtually every other Windows version ever shipped.Windows 7 Review Part 6: Performance
The funny thing about Vista performance, however, is that while it improved over time, few people even noticed since Vista-bashing had become a national pastime. Microsoft dramatically overhauled Vista performance, a process that culminated with the release of Vista Service Pack 1 (SP1) in early 2008. Disk file copy issues? Fixed. Startup, standby, resume, and shutdown speeds were all dramatically increased. Drivers were made more efficient, improving battery life. According to industry benchmarks, by the time SP1 shipped, real world Vista performance was on par with, in some cases superior to, that of XP.