This extension must be upgrade with the ability to playback .mp4 files with flash and the ability to playback streaming flash video, both .mp4 and flv.
Sorry, I have to watch for another editor. That sad, because most other things will work.
(If the video thing had work, it had been and Excelent! extension, but standard support is a must to get a grade average and above in my view.).
mp4 files are supported by the Media Manager plugin and are set for playback by Quicktime by default. The bundled FLV player does not yet support mp4, but a custom player can be specified in the Media Manager parameters.