Flash sucks, but it's on every single PC. Netflix has the power to get users to install Silverlight -- Microsoft made that pretty easy. Unfortunately you probably don't have their library and will live to regret it[1].
Adobe is also working on this idea with RTMFP (their newest streaming protocol)[2]
In fact few years there's been a company already doing this with a Flash Plugin (Yes dawg, there's a Plugin in my Plugin).[3] CNN use(d) it for quite a while.
I wouldn't bet anything on BitTorrent adding anything interesting here. The technology may be difficult but it's not as difficult as overcoming the huge barriers to entry.
The best we can hope for is that they create an open protocol the way they did with BitTorrent that browsers can implement over the next 5+ years.
1. http://en.wikipedia.org/wiki/Joost#Application_discontinued