I use Windows Explorer constantly. I like my directory trees.
AND my Classic gray color scheme.
Vista is a dud. I have it (the final version) on another computer. Seriously, wait at least for the Service Pack to come towards the end of the year if you have a choice. This thing is a step back.
There was an article somewhere blasting Vista's usability hit. Can't find it now, but they were dead on. "Add and Remove Programs" is now called "Programs and Features." (Like that's supposed to make more sense?) Changing your wallpaper is now hidden under Personalization, while Mouse Pointers still has it's own menu item... There's just some really stupid stuff here. It's like they're rushing code so hardcore that they skipped usability almost entirely.
Not to mention many anti-virus programs don't work.
Edit: Oh yeah, speaking of usability, IE7 also sucks. Why are the buttons all over the place? Why is Forward/Back on the far left side of the menu, Refresh/Stop towards the middle right, Home/Tools on the far right, etc...