At Microsoft Build, Microsoft released a developer preview of Windows 8. There are a variety of pre-beta downloads you can grab today if you want to check out the preview of Windows today. In addition to including the next version of Windows, you also get a chance to see Visual Studio 11 Express for Windows 8 Developer Preview.
If you do download the Windows 8 Developer Preview, be aware that the file sizes are large. The 4.8 GB download of the English 64-bit (x64) tools is bigger than a standard DVD. This means you need a large format DVD or to build a bootable thumb drive. I did a bootable thumb drive, which was relatively easy to create and even easier to install from.
I noticed there is also a 32-bit (x86) version available now as well. I've not downloaded it, but at 2.8 GB, it should be a bit easier to work with than the 64 bit version.
Do you want to see Windows 8? You can download it from the following link. It is pre-beta software, so only install it on a machine with nothing important already on it.