I've been successfully using Fusion 5 with Bootcamp since it came out. I upgraded to 6 today and it had me delete my VMWare Bootcamp file and recreate it. When I go to recreate it, on the "Choose a Boot Camp Volume" screen the BOOTCAMP disk icon has a warning icon next to it with the text "If another virtual machine is using the disk, it must be powered off first." No virtual machines are running and I've rebooted my Mac. I cannot get past the screen....if I select the volume and the "Create a Boot Camp Virtual Machine" option the Continue button remains grayed out.
Craig