This one's been kicking up for some time now, beginning years' back when several prominent Microsoft executives defected to Google when it was still a young upstart. The battle royale takes place on several fronts, most publicly in the search market where Google owns 65 percent market share. Microsoft's new search engine Bing is still a distant third with 9 percent market share, but has gained ground over the summer. Microsoft's forthcoming search alliance with Yahoo, No. 2 in the space, is expected to further toss a stake in the ground against Google when it comes to fruition next year.