The MOVs that I see playback glitching in QT10 are using H264 codec. The same MOV plays cleanly in QTPro7. These are MOVs exported from M100 Suite 2.1.
Here's an example from this morning. The top image is QT10, the bottom is QTPro7. Both players using the same H264 MOV file. QTPro7 does not exhibit the playback glitches that I frequently see with QT10 playback.
Jaeson