On a 2011 iMac when playing back R3D files Im also getting about half the fps I was getting before the OS X 10.7.4 update. Thats about 10-15fps without any corrections and quality set to 1/2 good. A week ago i was getting 25fps with a few nodes applied with the same settings. Downgrading to 10.7.3 didn’t help. I have been in touch with BMD support about this. Very nice guys, no fix yet though.
Really hoping this gets sorted by next week as its now seriously hurting my work…