Well ill be damned, i think ive found a solid solution to the cpu spike issue. The frame pacing bug is still there, but only with vsync on. I play with vsync off and its smooth I will do some more testing and then post up the fix in due course.
EDIT
Frame pacing remains spike free so long as the fps limit stays in place. With the fps cap removed cpu spikes are still present but not as bad as before.
EDIT 2
Ok spikes occur with frame pacing on or off. Solution for smooth gameplay is the fix i have coming + frame pacing on, vsync off, fps cap at 60, or frame pacing off, vsync on, fps cap at 60. I'm going with the latter, for now.
Whats the fix you have coming mate? Is it something we will have to download?