Today at the CES 2011, Microsoft presented a Windows 8 build running on an ARM test PC. The build was Windows 8 6.2.7867.
After taking a closer look at the CES presentation you will see the full Windows 8 build on the command prompt:
For the full list of Windows 8 builds: Windows 8 Builds Rumors + Officially confirmed
Update: Should you have missed the CES keynote by Steve Ballmer this year, here’s the full video:
The close-up shot above of build 6.2.7867 is taken directly from this presentation. You can verify this by taking a look at minute 4:04 in the last video (part 5).