Not that anyone will bother listening..
XP was no different and was hated on release. It was short of drivers, quite buggy and only really began to be accepted a year on when SP1 came out.
There was still a mass of Windows 98 users who objected to a properly written operating system stopping their shitty programs that tried to do dodgy things to memory from working. Gaming was faster in 98 for some time after the release of XP. There was also a shortage of drivers, and increased security - a proper NTFS filesystem, multiuser, SMP etc.
Does this sound at all familiar?
Since 2001 there are radically more threats on the Internet, dodgy programs, botnets etc. Like the Internet originally, there are parts of Windows (and Unix incidentally) that were designed for speed or ease of use over security and were more forgiving of programming errors.
Whilst Vista did have a number of unacceptable bugs, a large part of the public's dislike for it was due to a) a lack of drivers - people like Nvidia and Creative Labs did not pull their finger out for months after release, which is clearly unforgiveable b) Microsoft's usual trick of specifying inadequate hardware requirements - Vista will run quite well in 1GB, but don't try running large games or apps on it.. c) the beginings of proper security enforcement and user/admin separation and d) enforcing requirements on app writers that had been recommendations for years.
Users just want Things To Work. Unfortunately they're also unrealistic and expect stable, secure apps at the same time. This is not going to happen. The apps which don't work well under Vista/7 (including ones from Microsoft : bad form, there) are ones that didn't follow the guidelines anyway. Excessive numbers of prompts from UAC are also there because apps are poorly written - other prompts that previously weren't there are now included as they should be there (admin level changes).
Vista was actually stricter than 7 in some areas. 7 has been dumbed down, and if anyone has any sense they'll be running as a standard user with the UAC on high (enter password for all admin level changes).
For the idiots who go off into 'Ubuntu is lovely' lala land, note that Unix is still shit, just in different areas. X really needs a bit of an overhaul - it's not stunningly secure, just like windowing in Windows. When OpenBSD did the opposite to Microsoft's fault tolerant heap and enforced a strict heap, many apps fell over, including some quite old ones. OpenBSD is a good OS, but Theo et al have a lot more freedom to change it than Windows (Can you imagine the outcry if Microsoft did the strict heap change, or indeed the wholesale pf syntax change?)
Unix has many features that are designed well, but don't pretend it's a panacea.