Providence Equity Partners? $100m? This doesn't sound like a startup. And that means they won't get startup quality people to work on it. And that means they are doomed.
This is where NBC and Fox's content is going to be available online, so this company with no name will not be going away, unless it collapses before the launch. In the long term, the advertising revenues from NBC and Fox's online video should be very respectable.
As long as the shows are free to watch, it won't be a disastrous failure because there aren't many places to easily and legally watch online network TV. The best way to compete with piracy is to give your media away. If they insist on charging for everything, it'll fail.
Large groups of people aren't good at entrepreneurship. That doesn't mean a large corporation can't give a small group of people autonomy to go off and do their own thing. You don't get all of the benefits of being a startup, but you still get some of them.
I'm not sure those are examples of entrepreneurship as much as ruthless competitiveness. At least one of those defeats was proven to be done illegally. They're all over a decade old.
You ask Google, Apple, and Ubuntu whether Microsoft scares them.
I actually was not. Whether or not you approve of MSFT's tactics, you really can't accuse them of not being able to respond to market challenges.
Google may not be scared of them, but I would personally rather take my chances against NBC (for example) than go head to head with MSFT.