Ogg has advantages. Flash for video delivery has major disadvantages
Those poor disadvantaged guys at YouTube. They're disadvantaging all the way to the bank
Re: streaming efficiency, most C9 videos works just as good as MP3.
But here's my C9 video experience of FireFox. When I click on the mms: link, FF is confused and doesn't know how to handle that protocol. I even set up the protocol handler in FF -- not sure why it doesn't work.
When I click on the http: link, FF offers to download it for me -- or to open up WMP once the download is complete. It's so nice.
I see less hope for FLV on C9 though, with Silverlight streaming already here.