Darren should know the dangers of comparing things like operating systems to motor vehicles, Bill Gates certainly has. Darren does have a good point, Vista doesn’t have one single killer feature that appeals to everyone, it has thousands of killer features which appeal to different groups of people, and which other groups can’t see the value of.
For example – one of the killer new features for me as a developer is the way the start menu no longer creates columns going across the page when there are a large number of software packages installed. I had the “pleasure” of going back and using a Windows 2000 desktop last week, I can tell you now that a short amount of time doing that made me appreciate how much more productive I am on the Vista platform.
What operating system upgrades do is set a baseline which can shorthand discussions, for example, because I know that Vista is going to ship with WPF, WCF and WF I can simply say “you must be running Windows Vista to run this software”.
I think that everyone has forgotten that the thing that drives platform adoption – applications. Vista will make desktop applications sexy again – irresistably sexy, and that will drive Vista sales.