The great thing about the E3 press conferences is that, no matter whether they are good or bad, they make such a spectacle out of it all that it's always interesting. If the presentation is great, you get swept up in what's happening, and if it is terrible, you get to laugh at the blunders and follies.
Anyway, I feel I should point out other streaming options. I know that in past years, some people (including me) have had problems with the feeds suddenly freezing. GameSpot and Giant Bomb also have streams should any of those options in the original post stop working for you.