Looks like they are modelling W8 on their Windows phone interface.
Having used the Windows 8 Developers Preview for a little while now I can confirm that seems to be the direction.
It's horribly "retro" and very awkward on a non-touchscreen system, but I guess far from finished.
Fortunately there are 3rd-party mini-apps that can switch off the so-called "Metro" interface and get you back to a more normal desktop that you can use with mouse and keyboard.
That said, one of the systems I'm running it on is a pretty old and limited Dell desktop and it's working fine.