CU6. Apparently whomever got assigned to my case was less than compentant. I re-submitted my request, and got the correct build.
But I agree that having TESTED service packs at least every 6 months would be a welcome change.
As for CTP's in general. I don't have the time at the moment to mess with the release, nor do I expect that I will be ready for 2008 for at least a few more years.