Problem Installing Boot Camp Windows Partition on new Mac Pro
Finally got this working, thanks to a person named "turbostar" over on discussions.apple.com:


Re-run Boot Camp Assistant to remove the Windows partition and restore the full Mac HD as a single partition.
Run a PRAM reset (restart, while screen is still black, hold down ⌘+Option+P+R and keep them pressed until you hear the startup sound a second time).
Open disk utility and repair permissions on the Macintosh HD partition. TWICE.
Start Boot Camp Assistant again.


Seems hokey. With those instructions I thought I would also have to stand on one foot, point to my nose, rub my belly, and hope for rain. But it did end up working.