we are already being pressured by "layer 8" folks to start deploying Windows 8. We've started getting some of the new Dell hybrid ultrabooks that convert into tablets. They ship with Windows 8 on them, but our current stanadard image is Windows 7. Of course 7 isn't nearly as "tablet" friendly as 8.
Our initial tests show that the new x64 winpe doesn't seem to have the necessary pieces to use DISM and we can't figure out how to capture and deploy a Windows 8 image that we can use with LANDesk.
In our environment, currently using 9.5, we have been able to image Windows 8 machines with no issues. If you follow the Windows 7 sysprep articles in the Community, you’ll find it works just fine. I would use the winpe for Windows 7 to capture/deploy Windows 8. I have tested HII and without, and have experienced no issues. There are of course the stray devices that do not get installed by HII, but that is not a big issue. Let me know if you are successful.