It’s far too early for Microsoft to claim victory — or for that matter to claim anything more than a decent start. But Bing, the new search engine that the company rolled out less than two weeks ago, appears to have given Microsoft a nice bump in use.

Bing’s market share in the United States rose to 11.1 percent between June 2 and June 6, up from 9.1 percent the week before, according to comScore. Bing is also being used by more people — 15.5 percent of users — than before — 13.8 percent, comScore said.

Of course, these are very early days for Bing. ComScore, the research company, said it released the data because of the intense interest in the competition for Web search among Google, Yahoo and Microsoft. But comScore was careful to note that the results should be taken with a grain of salt. New products often enjoy a bump in use from the publicity associated with their rollout, and Microsoft is also heavily promoting Bing on television and on the Internet.

“These initial data suggest that Microsoft Bing has generated early interest, resulting in a spike in search engagement and an immediate term improvement to Microsoft’s position in the search market,” wrote Mike Hurt, a senior vice president at comScore. “So far it appears that the lifts in searcher penetration and engagement have held relatively steady throughout the five-day period.”

Microsoft declined to comment on comScore’s numbers.

In some sense, the numbers suggest that the challenge for Microsoft begins now. The company got people to notice Bing. Now it has to not only sustain but also increase its early momentum. And it has to convince users that Bing works as well or better than Google, or those who try it — because it is new or because they have been prompted to by the ad campaign — will not stick with it.

“The ultimate performance of Bing depends on the extent to which it generates more trial through its extensive launch campaign and whether it retains those trial users,” Hurt wrote. “It appears it is off to a good start.”

For all the confidence typically emanating from the Googleplex when it comes to search, Google apparently is not ignoring Microsoft. Speaking at an investor conference, Patrick Pichette, Google’s chief financial officer, said the company’s top executives are closely reviewing Bing.

Of course, appearing to be concerned about Bing dovetails nicely with an important Google goal: convincing a growing chorus of regulators and advocacy groups concerned about Google’s market power that the company faces plenty of competition.

Perhaps Microsoft’s biggest success around the release of Bing is that much of the conversation about search now revolves around the competition between Google and Microsoft. Never mind that Yahoo’s market share is still roughly twice as large as Microsoft’s. No doubt Microsoft’s marketers like it that way. (NYT)