It has been an interesting day in the IT world. Opening the month of May a couple of interesting stories involving the rivalry between Google and Microsoft are playing through the news today.

The first story demonstrates an Amazon migration from Google based results to those gleaned by the new MSN Search engine, Windows Live. First noted by Aaron Wall over at Threadwatch, A9 and Alexa have both replaced Google’s results for Windows Live.

Amazon’s move away from Google is indicative of a more general fear of Google’s diversification and growth into non-search related markets such as its online payment system and offline advertising ventures.

An unrelated WSJ report on April 21st (subscription required for WSJ) notes how the online auction house eBay is seeking partners among search firms to bolster itself against the growing threat Google represents.

“After years of working closely with the search giant, eBay last year became alarmed as Google started assaulting its turf in multiple ways,” the report stated. eBay has been in talks with both Yahoo and Microsoft since early autumn 2005.

Another story touching on the rivalry between Google and Microsoft was reported in today’s New York Times. According to the report, written by NYTimes technology writer Steve Lohr, Google is lobbying both the EU and the US Justice Department to examine Microsoft’s most recent browser, IE7, over the placement of a search-box directly in the browser. While the search engine queried by the IE7 search box can be set by the user, it is set to default to Windows Live.

The placement of a search box in the browser is reminiscent of the way Microsoft drove Netscape out of the market by originally bundling Internet Explorer into its Windows suite in the mid 1990’s. While that move virtually destroyed Netscape’s burgeoning browser business, it landed Microsoft in EU and US courts fighting anti-trust suits and the repercussions of those suits for much of the previous decade.

“The market favors open choice for search, and companies should compete for users based on the quality of their search services,” said Marissa Mayer, the vice president for search products at Google in an interview with Lohr. “We don’t think it’s right for Microsoft to just set the default to MSN. We believe users should choose.”

Though Google has taken its concerns to EU and US anti-trust investigators, there is no guarantee that an investigation will be undertaken by either government.