I mostly agree with Tofi's take on this. On the whole, MS has been very successful in the OS arena. Having worked with multiple versions of Linux and Unix, I tend to see each OS having its own strengths and weaknesses, so you can't really discount an OS as a whole without analyzing its various features and comparing them with other OS.
My few additions to Tofi's list are as follows:
That's just bad propaganda. Windows ME wasn't really an OS, it was just something bad, leaked out like a by-product :D
- Windows 3.1 (including windows for workgroups) - success
- Windows 95 - success (revolutionary in multiple ways)
- Windows NT 4 - success
- Windows 98 - failed at the beginning, but Windows 98 SE (Second Edition) fixed most problems.* Windows ME - failed miserably, primarily due to multiple betas released in the same year, and MS's move to the NT kernel and lack of sustained support for ME (shelf life was around 8 - 9 months)
- Windows 2000 - success
- Windows XP - success
- Windows Vista - failed at the beginning but was later fixed once SP's were released
- Windows 7 - Success
Now on the server side: * Windows NT 4 server - success * Windows 2000 server - success * Windows 2003 server - success * Windows 2008 server - success
As you can see the overall progression has been excellent with a few hiccups along the way. I do agree that their timing sucks chunks and they are always playing catchup. But that success-failure-success theory is just some disgruntled pundit sitting around with an agenda. I propose to ban them :)