Flash Player now supports H.264 (mpeg4)! Flash video just got a major kick in the pants. You can actually load .mp4, .m4v, .m4a, .mov and .3gp files using the same ActionScript API that you currently use to load FLV files. All existing code should now work with these new files formats. If your video player is run off dunamic data you should be able to just start dropping in quicktime and mpeg-4 files. Crazy!
A new version of FMS is coming out soon with streaming support for these file formats.
Check out this post by Tinic for a very detailed explination of what the update includes. I guess it was planned for Flash Player 10, but they got it in this newer version because customers really wanted it.