I have just finished downloading and installing the official beta of WIndows 7 from Microsoft.
For me personally the install took a long time but I am sure that is due to the fact I upgraded and have quite a lot of crap on my computer.
Overall I think the performance is a lot faster than Vista and have not faced many problems yet.
One thing that is quite annoying is that the user foler has now been replaced with something called "Libraries", you can still access the user foler but the most common folder you will use is the libraries folder, this only contains Documents, Picture and Videos. Ok if you use those a lot but I personally use the Download folder a lot which isn't included.
The taskbar is a lot cleaner now, with applications show as icons, when you hover over the icons a panel will appear with the application window(s), a nice touch is that all the tabs used in IE are show as seperate windows making tab selection easier.
The notification icons have taken a more black and white approach from what I can tell on my system which is ok but does look a bit bland.
The system rating has been updated with the highest score now 7.9.
Here are some photo's I am sorry for the lack of quality as they were taken with my phone.
[IMG] http://i42.tinypic.com/2wqhmht.png [/IMG]