The issue with whether Google is or is not a monopoly isn't merely its search dominance: It's Google's ability to control online advertising and, increasingly, what we read or don't read.
This isn't entirely Google's fault, but a company whose goal seems to be to index and, if possible monetize and even appropriate, all the world's public information is going to run into antitrust problems eventually, right?
It used to be there were hundreds of thousands of gatekeepers to the world's information stores. Think of these people as being newspaper editors, TV and radio, book publishers, corporations, even the proverbial "man on the street."
All these people are being rolled up into the colossus that is Google. People rely more and more on its search engine to tell them what to think. We don't troll the Internet as much as we used to looking for information, we just let Google do it.
Google's results are a big deal in determining what people read and, increasingly, in what people write. Search engine optimization, which is to say the mystical art of giving Google what it wants, is a growth industry that has already changed the nature of the online content we read.
Google has yet to really develop a computerized sense for content quality and it can be hard to create a search that provides the desired results. Google is working on this, of course, even as it gobbles up all the information it can find online and, increasingly, offline as well.
On the advertising side, Google has played a huge role in what many see as a total collapse of the model that had advertising paying for free or low-cost content for the masses.
Google now makes that content available, but doesn't really contribute much to paying for its creation. That may turn out to be a good thing or a bad one, but right now it's a disruption with no end in sight.
Antitrust regulators will look at this merely as a business issue--is Google too big for the good of the marketplace. What they really should be asking is whether Google is gaining too much control of another marketplace--that of ideas.