Microsoft held 8.23 percent of the search market in June. That puts Microsoft just slightly behind Yahoo with 11.04 percent.

Google still dominates the U.S. search market, but Bing appears to be making an impact on the search giant. Microsoft is spending $80 million to $100 million to market Bing. In April, before Bing was launched, Google had 79.07 percent of the search market. In June, that slipped slightly to 78.48 percent. Microsoft's U.S. market share was 7.21 percent in April.

"At first sight, a one percent increase in market share does not appear to be a huge return on the investment Microsoft has made in Bing, but the underlying trend appears positive," said Aodhan Cullen, CEO of StatCounter. "Steady if not spectacular might be the best way to describe performance to date."

Bing Shakes Up Market

Examining the weekly search-market trends for June, Cullen noted that Microsoft sites -- which include Bing, Live Search, and MSN Search -- peaked just after the Bing launch at 9.21 percent. Bing then saw a dip during the following two weeks, but staged a comeback in the final week of June to 8.45 percent.

Globally, Microsoft appears to be making modest headway, rising from 3.08 percent market share in April to 3.30 percent in June. In the same period, Yahoo fell from 5.48 percent to 5.15 percent globally. Google still dominates the global market with 89.80 percent.

While talk of a Microsoft-Yahoo deal has quieted since Bing launched, talk of Microsoft competing more effectively with Google is on the rise. There are even rumors that Google cofounder Sergey Brin has assembled a team of top engineers to work on urgent updates to the site in response to Bing.

Building Advertiser Credibility

The latest buzz on Bing is that the new search engine might catch on with Internet advertisers or mobile users. That in itself would be a blow to Google. But Bing is focused on helping consumers shop for goods, do health-care research, and otherwise help them make decisions. Hence, the term decision engine.

Microsoft is likely waiting for comScore's latest search-market rankings for confirmation. You can't rely on any single source to give a definitive picture of the market and have to wait for a data consensus, according to Greg Sterling, principal analyst at Sterling Market Intelligence. However, he said, this further confirms some of the early data from comScore, Hitwise and others showing Bing's early traction.

"It's encouraging for Bing and Microsoft, but there needs to be continued growth and momentum over the next few months before we can say with any degree of certainty that Microsoft has a hit on its hands," Sterling said. "The positive PR by itself, however, will help Microsoft gain more credibility with advertisers and boost the profile of AdCenter."