Bing Leveling Off While Yahoo Slips: Nielsen

The popularity of Microsoft’s Bing search engine appeared to be leveling off in December, but Yahoo’s market share is definitely slipping, according to the latest figures from a leading analytics firm.

Microsoft (NASDAQ: MSFT) Bing pulled 9.9 percent of all U.S. searches in December, The Nielsen Company said in a blog post Wednesday.

That’s down from 10.7 percent in November, a loss of 0.8 percent. However, though it may be a little harder to perceive, Microsoft’s soon-to-be partner Yahoo (NASDAQ: YHOO) has been slipping more precipitously.

In December, Yahoo slid from 15.3 percent of searches to 14.4, a loss of 0.9 percent. While that is barely different from Bing’s decline in December, Yahoo is down from 17.1 percent share in July, after two months of Bing’s availability.

Meanwhile, by Nielsen’s count, Microsoft has been seesawing back and forth at around 10 percent share since August, when it was also at 10.7 percent.

As usual recently, Google’s (NASDAQ: GOOG) search engine is the beneficiary of Yahoo’s slow slide. It picked up 1.9 percent in December for a total 67.3 percent share, up from 65.4 percent in November, Nielsen said. That is also up from 64.6 percent in August.

Neither trend is good for Microsoft, though it broke the billion searches in a month barrier in August, with a total of 1.2 billion.

In December, despite months of Microsoft’s quirky “decision engine” TV ads, Bing’s search totals were only 986 million, while Google had 6.7 billion and Yahoo 1.4 billion. Bing’s searches for November totaled 1.07 billion, Nielsen said.

However, the gradual slide in Yahoo’s popularity with users may be more troubling, particularly for Microsoft, which last month finally inked its search in exchange for ad revenues deal with Yahoo.

Under the terms of that deal, which is still pending regulatory review, Microsoft Bing will provide the search infrastructure that serves Yahoo sites.

Microsoft has not said when regulatory review of the ten-year deal will be complete, but officials have said they are looking out for that official okay early this year.

However, as that day looms closer, Yahoo’s share continues to deteriorate. If the combination of the two companies’ market share had taken place in August, it would have been 26.7 percent.

If, instead, the combination had occurred in December, Bing’s combined market share would only have been 24.3 percent.

In the meantime, Google continues to pull further ahead.

Stuart J. Johnston is a contributing writer at InternetNews.com, the news service of Internet.com, the network for technology professionals.