I think every one of these people have a very short memory. I have been doing computer support for over 15 years. Most of that supporting end users at the consumer level and enterprise level. My first enterprise/corp task was to upgrade windows 3.1 computers to windows 95 for "outlook" email. I've have deployed windows 2000 and windows xp as major projects to help corp. standardize their hw and software platforms. I know the ins and outs of te operating systems pretty well.
there are some basic truths to had. It doesn't matter how well an OS is designed, tested, and maintained the user will find a way to break it. The user will always find something doesn't work (os compatibility) no matter how much time is spent making sure that compatibility issues are worked out. Lastly, you will not be able to satisfy everyone.
For the consumer, going from win9x to xp was a huge experience. It was a great step forward in stability, user interface enhancements, hw support. Still there were new bugs found. USB hw, especially had issues. Driver for hw was very lacking. Then there were several security holes found. From the enterprise side, there was a very big issue with blue screen error resulting from image deployments. Out comes the first sp for xp. Fixed a large number of bugs, performance issues, included a large number of hw drivers, and security fixes. It wasn't until sp1 that most corp. started working seriously on deploying xp.
For the most part, going from nt to 2000 was just as big of an experience for corp. users as was consumers upgrading to xp. However, going from windows 2000 to xp wasn't as nearly a big transition. It was a more natural evolution.
Then there became the litany of security holes in xp, Internet explorer, and other MS applications. There became a very big concern for security improvements. Service pack 2 for xp made many changes to the os including a better firewall, improved Internet explorer, and many, many security fixes. Out of this came a new mindset regarding a ground up focus on security.
Vista was developed to be more secure. To offer a lot more internal enhancements. At this there have been very successful. Looking at our own support forums, though I see a familiar trend. Users are finding ways to break it. Users are finding things that aren't compatible. Not only is the a self evident truth, but the exact same thing was experienced when xp was released. Slightly different issues and slightly different fixes are required for the same general problems.
Does vista have problems? Sure it does. Are they anything new compared to other operating system launches? Nope. Been there, done that, bought the t-shirt. Will sp1 fix everything? Probably not. It will go a long way to resolving many of the complaints out there. It will fix a large number of things people want to be addressed.
The only thing I think MS failed at was bringing about enough new technology in vista to give it the "wow" factor. I know they dropped a number of enhancements for a variety of reasons. I hope in the next iteration of vista they are able to bring those technologies to the platform.
So to those that are quick to bash vista for its short comings and issues, please take a look in the mirror. This isn't the first os to go through with this. Please temper your tirades with quiet reflection on OS history.