I've now installed the Windows 7 Public Beta. The installation was probably the quickest of any MS operating system since DOS.
It detected my dual monitor setup no problems
It's definitely faster than Vista, at least subjectively.
However they seem to be going further down the "Your computer as a toy" and the "change for the sake of it" route. In Vista I run the grownups (or Classic) menu. 7 has only the children's menu
Along the same lines, the Explorer status bar has been replaced by the detail pane. This gives the same info, but takes up more space, and, of course is turned on and off via a different route.
UAC is definitely lass intrusive.
It found my network and connected to my other machines without the need for any user intervention, which was quite impressive.
There is a major bug in the login screen which means it takes around 15-20 minutes to log in - but then it is a Beta version.
Some tasks are even harder to fin than they were under Vista, but others are much easier.
Keep in mind that these are only preliminary observations - I've been using it for a couple of hours. I would say that at the moment, I'm a bit disappointed, but there is a general feeling that it's improved in some ways.