Well. I'll tell you the reason :-).

I'm working on the infrastructure for streaming more than 20 radio channels. Content
from the last 30 days should be available in several bitrates for a variety of players,
not only Flash. This content totals about 4 TB or more at any one time. The reason for
choosing AAC/Mp4 is because of compatibility and ease of compression. We simply don't
want to add yet another format to store (flv). Since flash can play AAC/Mp4 now we want to
use that with the Flash player.

I've tested the h264 module and it seems to be pretty fast and working well. My only problem
is the mirroring on demand through nginx by using proxy_store. I guess there are other ways
to do this but this solution was SO simple and elegant if not for this little problem which may very
well force me to find another solution.

Any ideas?