I have been doing the Mpeg Streamclip "Save As" to .mov file for a while now. It still doesn't play back optimally in Adobe Premiere CS4..but it is workable.
But, I just wanted to let everyone know.. I just downloaded the Demo to Adobe Premiere CS5 and the .MP4 files play back AWESOME! They actually play more smoothly in CS5 than I have ever seen HD video from a small camera play back!