Vista is more self healing, less likely to crash, and so on. And my experience across hundreds of machines backs this up. As well as independent numbers, not just Microsoft’s.
Hardware requirements for Vista are on par with Leopard, and Leopard can’t join 90% of managed networks because Apple shipped it with critical problems in Kerberos. Oh, and Vista ships with a half decent firewall.
Again, the real problem is that people got used to not upgrading their OS, of sticking with the NT5 family since 1999 (yes, 8 years prior to the Vista launch was the last major version increment for Microsoft software). Guess what? It had very steep hardware requirements at the time too. In fact, when NT5 first launched, it was recomended for performance reasons that you used dual processors – imagine that. But, again, eight years ago and nobody remembers that.
Look at the competition: Mac OS 9 launched basically simultaneous with NT5 – and then OS 10.0, 10.1, 10.2, 10.3, 10.4 and now 10.5 came out. Solaris 7 launched a year before NT5 and since then it’s been Solaris 8, Solaris 9 and Solaris 10.
Do I think Microsoft could have done better with the Vista launch? Of course! But given the competition is worse, I don’t think there’s much real room for argument.