counter points: 
1. most content isn't live-streamed.
2. content that is live-streamed fits very well to p2p , which is very cheap , and might even become embedded in flash. 
3. the buffering issue holds some of the characteristics of disruptive technology:worse in viewing quality , but better in other dimensions - viewing options /price / experience. and as any disruptive tech , it's always improving. 
4. regarding 3 internet video service providers :  given a lot less customer lockup then cable companies , the competition between those 3 are better . 
5, Alot depends on which advertising model(web vs cable) , will be able to offer better results.