It's not even close.

Fresh data out of comScore shows that Microsoft's (Nasdaq: MSFT) Bing is still a distant second in the search engine race.

Thankfully for Bing this is more of a marathon than a sprint. The latest comScore research shows Google (Nasdaq: GOOG) firmly in the lead with Bing practically unrecognizable in Big G's rearview mirror. Their market share was essentially unchanged in March relative to February. Yahoo! (Nasdaq: YHOO) took a small step back. AOL (NYSE: AOL) took a small step forward. IAC's (Nasdaq: IACI) joins Google and Bing by running in place.

However, there isn't a lot that one can discern from the subtle month-to-month gyrations. The real changes take place over time, so let's dig up some of comScore's earlier reports to see how things have played out over the past two years.

March 12
Feb. 12
March 11
March 10
Google 66.4% 66.4% 65.7% 65.1%
Bing 15.3% 15.3% 13.9% 11.7%
Yahoo! 13.7% 13.8% 15.7% 16.9% 3% 3% 3.1% 3.8%
AOL 1.6% 1.5% 1.6% 2.5%

Source: comScore.

There were nearly 18.4 billion search queries performed in this country last month according to comScore; that's 8% ahead of where we were last year.

Google has been able to gain ground in each of the past two years, but check out Bing. It went from 11.7% of the market two years ago to 13.9% last year and up to 15.3% now. Google may command nearly two-thirds of the country's search volume, but Bing is in fact gradually narrowing the gap.

The problem for Bing's breadth is that it also watches over Yahoo!'s search business. Microsoft is paying big bucks for the incremental exposure, but Yahoo! is going the wrong way. Bing's market share may have gained 360 basis points over the past two years, but Yahoo! has retreated by 320 basis points. Things get uglier when you just consider Yahoo!'s precipitous slide over the past year alone. Since March of last year, the combined market share of Bing and Yahoo! has fallen from 29.6% to 29%.

Obviously it's not Microsoft's business to keep Yahoo! afloat. At the end of the day, Bing itself is still improving. However, until Bing's growth comes at the expense of Google -- and not simply its search partner -- Microsoft will have a long way to go before Google breaks a sweat.

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