That sure would be amazing, but I doubt it.
I only heard of kvm a few days ago, but as far as I understand, kvm and qemu share a lot of code and functionality.
When talking about virtualization, it is mainly the cpu that is being virtualized, and everything cpu-related is executed with nearly-native speed inside the guest OS when being virtualized.
qemu, when run on x86 architecture with the kqemu kernel module, can also achieve near-native execution speed.
But this is only one part that is needed for running games.
I don't know how kvm virtualizes other hardware, but as far as qemu goes, it *emulates* a few pieces of hardware, e.g. a Sound Blaster 16 and a an old Cirrus graphic board and network interface cards.
I managed without problems to install Windows98 with qemu and play some very old Windows games; I am talking about DirectX 3 stuff here. I don't think accelerated 3D graphics will be possible.
However, I maybe wrong, and I would be glad to be corrected on this issue.