Wow, tight loops are so 80's man.
You shouldn't need to do loops like that in Windows. A0;Try either the hi-res timers, or perhaps even WM_TIMER could do.
All right, I wrote the perfect game loop that uses minimal CPU time. It's implemented in the new game and running at 60 frames per second. It uses barely any CPU time (on a 3Ghz machine) so it plays nice with other Windows programs that happen to be running.
It's actually a user customizable loop, so if the user actually wants to use 100% CPU then there is a setting for it. I know, that's retarded.