Flash wouldn't help here. It would actually make it worse, since it requires custom backend for live streaming. Apple is simply pushing out files, and Akamai is simply serving HTTP requests. It scales well, since Akamai is already set up to host tons of HTTP content. Apple published the standard with an industry recognized standards body, not their fault other companies haven't chosen to implement it.

You can see Akamai's stats for streaming here:
http://www.akamai.com/html/technology/dataviz3.html

It's shot up like crazy since the event started.

I'll hold back any feedback till it's over though, still plenty to go.