FullHD (1920x1080) MPEG-2 imported directly into iMovie 08 from a JVC GZ-HD7 camcorder.
The project was then exported to H.264 using a recipe from my DVC Guide to iMovie 08 Editing. Exported and uploaded as: 720p30 at 4800 kbps with 48kHz stereo audio at 192kbps. I increased saturated by 4%.
Previous tests show clips edited by iMovie 08 look just as good as the same clips edited with FCP. Moreover, HD DVD's I've made from iMovie movies look fantastic -- many times better than this very low bit-rate movie.