Ben Edelman has done a truly exceptional job documenting the anti-trust issues involving Google's advertising.
NBC is not a monopoly, Google is. Google makes Microsoft's old monopoly look like a walk in the park. Google not only has the most used search engine but controls or has a majority chunk of the online advertising market flow through it (at least in the US, I'm sure there are exceptions on a country by country basis.) Additionally they now have what is likely to be come the #1 mobile phone operating system and potentially what could become the #1 web browser.
People go to Google to look for stuff. Lets say your business advertises on Google (mine does), and Google wants to do the same thing as your business does. Thanks to either their existing infrastructure or that you are advertising on their platform they know everything about how your business gets traffic. With the wave of a magic wand all of those search keywords and display ad placements are now directly to Google's new competitive service. I have seen Google do this in multiple markets, including my own. How do you compete against Google? You can't. Virtually every user wanting something specific comes from search.
That is an incredibly powerful monopoly, much more so than Microsoft's was.
Areas Google has already used this to their advantage: Google News (vs multiple news sites), Google Finance (Yahoo Finance and others), Google Shopping (infinite shopping sites), Google Health (WebMD etc), Google Places (remember the whole Yelp review jacking thing), and so on.
Unlike Microsoft, Google is actually putting out exceptional products and I am very thankful for that. But, a monopoly is a monopoly, and if anti-competitive practices are involved (strongly likely) US law has something to say about that. Thus any disagreement with this issue lays with US law rather than Google or the FTC.
By the way, I strongly recommend what Ben Endelman has written about this subject. I would take a guess he figured this out first.
(If I recall correctly Google was caught here telling lies)