RE: Television networks block Google TV from accessing web-based content (update)
Google, just like Microsoft a decade ago, has butted into a highly lucrative space where the business model is paying for content access as well as selling advertising.
Google TV essentially helps kill part of the revenue stream, which is the cable subscription. Just like with books Google has gotten ahead of its skis. This is bad business planning on Google's part and poor execution of this strategy. Again they forgot that just because something is technologically possible it doesn't mean it's going to be supported by the existing businesses.
I agree that eventually content is going to be distributed via the internet and people are going to browse linked television streams with hubs that aggregate the "channels"
If Google's model is to create a wide distribution of ad-only supported TV they are in trouble. A bunch of very important content is not sold for ad revenue only. Google has a choice - do they become the souped up YouTube distributor for the long tail of low value content or do they introduce a subscription model for TV. What happened below shows that they didn't really think this through.
Broader Discussion: http://www.engadget.com/2010/10/21/television-networks-block-google-tv-from-accessing-web-based-con/