This is pretty exciting. Xen will probably have something similar soon. I couldn't ever get my setup working with Xen (Intel 3770 non-K) but with the amount of work involved - hammering away at the kernel parameters, rebooting, trying again, discovering yet another configuration file to edit, reboot, try again, discovering that grub2 didn't properly build the new grub.cfg, etc - something much more simple is always welcome. I might have to switch over to QEMU from Xen just to give it a shot.
No announcement yet.
QEMU 1.5 Supports VGA Passthrough, Better USB 3.0