I'm still batteling to get the QuakeLive stutter free. In Q3 all I needed to set was:
1) r_displayrefresh 75
2) com_maxfps 75
3) 1024 x 768 res
4) m_filter 1
5) cg_fov 85

But now in QL these values doesn't smooth out the graphics at all.

Is this due to input lag from the mouse side? (like the mouse needs to be set to a higer response time)
Is the FOV causing this on the 1024 x 768 res?
Or is this because the game runs in a browser?
It doesn't look like there is a cure, as I've asked this question on the QL Forums too.