Anyone can grab a copy of the Windows 8 Developer Preview here: http://msdn.microsoft.com/en-us/windows/home/
I'm downloading it now, but it's slow going.
The preview has the new Metro interface which probably looks better on a tablet. Underneath all that is a normal Windows interface that looks a lot like Windows 7 still. I guess that could change.
There are some early screenshots here:
- Windows 8 Developer Preview Screenshots, Part 1
http://www.winsupersite.com/article/windows8/windows-8-developer-preview-screenshots-part-1-140548 - Windows 8 Developer Preview Screenshots, Part 2
http://www.winsupersite.com/article/windows8/windows-8-developer-preview-screenshots-part-2-140549