Hands on: A Mac fan takes on Vista... vista via bootcamp from a Mac. No surprise which one comes out on top of course, though the way that I read it it wasn't due to a glaring bias towards mac, the article seems relatively fair and balanced to me. Some of the critisism can also be boiled down to familiarity. If you're used to hitting a key combo to get your widgets up then not having that will seem like a bad thing. If you've never had key-combos, you won't miss it (as an example).
Course, if you're a Vista fan I'm sure you'll disagree with some of the assertations.... feel free to discuss here of course!