ComScore released its December 2010 search engine rankings today and the good news for Microsoft is that its "decision" engine, Bing, continued its steady market share growth. Bing ended 2010 with 12 percent of explicit core search share, a full point higher than its 11 percent share in July. Apparently, the $100 million that Microsoft allocated for Bing advertising is working.But there's a slight problem \u2014 well, two problems actually. Microsoft search partner Yahoo \u2014 the company now known more for layoffs than anything \u2014 has seen its search market share drop each month since August, finishing the year with 16 percent share, according to comScore. At the same, Google's search share has grown steadily. Google ended the year with 66.6 percent of the explicit core search share, almost a full point higher than its share in July, according comScore.So even though Bing is on the move, it is weighed down by the slipping Yahoo. Together they've been stuck at 28 percent combined market share for six months. It's one step forward, one step back. Meanwhile, Google's market share has grown at the same pace as Bing.A lot of this must be chalked up to human habit. Google does not advertise its search engine because it does not need to, at all. The company enjoys the advantage of our habitual instinct to "Google" something. And regardless of Microsoft's funny and perceptive ads warning us about Google's tendency to dump search results haphazardly on a page, the ads are not turning users away from Google for Web search. Yet it's not from lack of trying by Microsoft. On the advertising front, Bing is everywhere. TV commercials and radio spots abound. It is all over sports arenas, and has sponsorship deals with sports teams like the Seattle Seahawks and the WNBA's Seattle Storm. Bing sponsored Lebron James' ESPN show in July where he decided to go to the Miami Heat. It even sponsored "The Simpsons" for three months in England. Microsoft has $100 million invested in Bing marketing and will basically pimp out Bing to anyone who will have it. You can't miss Bing if you try. But the pimp-fest aside, Bing is one area where Microsoft is cutting smart search deals (with both Facebook and Twitter recently) and being innovative. The way Bing organizes information and images on a results page reduces clutter and is more intuitive than Google, which hasn't made significant renovations to its search results page in God knows how long. So while Bing's advertising warning about Google "search overload" may not be changing user behavior, it is a message Microsoft will keep hammering home. It's a pretty good card to play, after all. Eventually, more users will realize that Google's search results are sloppy, and maybe they'll give Bing\/Yahoo a chance.What do you think? As Microsoft and Yahoo finish building out their search platform, will the Microhoo united front reduce our "Googling"? Or is Google destined to be the king forever?Shane O'Neill covers Microsoft, Windows, Operating Systems, Productivity Apps and Online Services for CIO.com. Follow Shane on Twitter @smoneill. Follow everything from CIO.com on Twitter @CIOonline. Email Shane at email@example.com.