There are a few things I don't like about 7. For instance, I don't like how the Pictures link now goes to the Pictures library. Really this goes for all those libraries.
This seems like a good idea at first until you realize that anything in your libraries is available on Windows Media Center. There is a reason I have pictures in my own Pictures folder rather than the Public Pictures folder. So to prevent my eight year old stepson from seeing them via Windows Media Center, I have to take my personal Pictures folder out of the library (I tried unsharing it from the WMC interface, but all it does is take it out of the library). Now it is annoying when I am trying to get to my Pictures folder because the easy link that shows up in most windows and dialogs just takes me to the Pictures library. I usually have to go through the folder hierarchy and drill down to get where I want to go.
That seems like a step back rather than forward.
That said, the new taskbar is completely awesome. Like the Mac OS X dock, but better.