Google, Facebook and Amazon have proven virtually unassailable, regardless of who's taken them on.
Lucy Nicholson / Reuters / File
The Internet has long been held up as a model for what the free market is supposed to look like—competition in its purest form. So why does it look increasingly like a Monopoly board? Most of the major sectors today are controlled by one dominant company or an oligopoly. Google "owns" search; Facebook, social networking; eBay rules auctions; Apple dominates online content delivery; Amazon, retail; and so on.
There are digital Kashmirs, disputed territories that remain anyone's game, like digital publishing. But the dominions of major firms have enjoyed surprisingly secure borders over the last five years, their core markets secure. Microsoft's Bing, launched last year by a giant with $40 billion in cash on hand, has captured a mere 3.25% of query volume (Google retains 83%). Still, no one expects Google Buzz to seriously encroach on Facebook's market, or, for that matter, Skype to take over from Twitter. Though the border incursions do keep dominant firms on their toes, they have largely foundered as business ventures.