If you're thinking about taking the new Windows 8 Developers Preview for a test drive, you may consider watching this video.
Dual booting Windows 7 with the Windows 8 Developers Preview is pretty straight forward and not unlike we've all done dual boot scenarios in the past. Some folks have reported problems and I really have no explanation as to why, I actually got through it pretty easily on my first try, using a fully patched and updated version of Windows 7 32 bit Ultimate from within a Virtual Machine in Oracle's VirtualBox.
Good luck and best wishes to those who try. I will be doing another on removing the dual boot of Windows 8 from Windows 7 leaving only Windows 7 remaining soon.... I hope.
Regards
Randy