• by Wendy Davis , Staff Writer @wendyndavis, February 4, 2008

Now that Microsoft has put Yahoo in play with a $44.6 billion bid for the company, Google is ratcheting up the anti-Redmond rhetoric, arguing that Microsoft's antitrust history is reason alone to be wary of a deal.

"Could Microsoft now attempt to exert the same sort of inappropriate and illegal influence over the Internet that it did with the PC?" Google counsel David Drummond wrote on the Google blog. "While the Internet rewards competitive innovation, Microsoft has frequently sought to establish proprietary monopolies -- and then leverage its dominance into new, adjacent markets," he warned.

Microsoft's counsel Brad Smith predictably counters that with an estimated 75% of global paid search revenues, Google's hardly in a position to complain about a monopoly.

Google also reached out to Yahoo this weekend with a proposal to team up on paid search -- a move that appears to even further entrench Google's power -- according to a report in The Wall Street Journal.

But there's a big difference between the growth of Google's search engine and Internet Explorer. Google continues to increase market share for the simple reason that consumers prefer its search engine. In other words, when Web users vote with their mouses, they opt for Google based on its results -- and not any anticompetitive business decision by the company. On the other hand, Internet Explorer came to be the major browser because Microsoft bundled it with Windows.

This isn't the first time Google has taken aim at Microsoft on antitrust grounds. Last year, Google filed a confidential complaint against the software giant in which it argued that Microsoft's operating system slowed down Google's desktop search, according to The New York Times. (Microsoft's Smith told the Times that the company had modified Vista in response to concerns of Google and other companies.)

It's understandable that Google would be especially nervous now, given Microsoft's history. At the same time, regardless of how Google came to its position, there are serious risks to any one company dominating search engines -- which for many users are the gateway to all online information. If Google decides to lower a Web site's rank, that site can disappear from the organic results pages -- as famously happened to KinderStart.com, which sued Google over the matter several years ago. (The site appears to now be reinstated.) If a heated rivalry among search engines serves no other purpose, the competition at least makes it less likely that any one search engine will arbitrarily decide to stop linking to particular Web pages.