From Sept to Dec, I used WDP side by side with Win7 SP1... But since the last month or so, I'm using it in a VM (VMWare Player; can't install it in VirtualBox 'coz my processor doesn't support VT-x) I suggest you wait for the Beta and install WDP in a VM.
My CPU also doesn't support VT-x so only way to test WDP is install as main OS, Dual OS or to find Virtualization software who doesn't require VT-x
As of now, only VMWare Workstation and its free alternative VMWare Player lets you install Win8 without needing VT-x.
I trust Jaycee, so after she put up the build-string, I post about it in PCBeta & Neowin within 5 mins........ LOL, all hell broke lose
Because the build number is (generally) incremented everytime there is a compile. So the reason for the build jump is most likely because of last minute bug crushing.
Little Secret: In the Windows Developer Preview, start Windows Explorer and go to "C:\Windows\Offline Web Pages". The Ribbon will desappear and the Windows 7 Toolbar will be in there.
Wish I could somehow have the Aero and all the aero-related changes of Windows 8 in Windows 7..!! That would be so great! I will skip Windows 8 then!
So, if i have WDP installed i'll be able to upgrade to beta when available? you know, without having to erase the whole thing... sorry if this is off topic and about my english