Microsoft's internal data credits the launch of its new Bing search engine with an 8 percent boost in unique visitors during June.

It's been clear for a while that Bing's launch produced gains for Microsoft during its initial month, but the degree to which that gain was produced by those strolling by as a lark or by those actually using the service daily was unclear. Microsoft released data Monday claiming an 8 percent gain in unique users during the month, and said "based on our own polling, we have also seen the number of people 'likely to recommend' Bing double in our debut month."

Microsoft relaunched its search engine business in early June with the introduction of Bing. The company confirmed that the data outlined above refers to June 2009 as compared to May 2009, prior to the launch of the new service.

Three times as much traffic landed on Bing Shopping during the month, and Bing Travel has increased its traffic by 90 percent. Advertisers also saw some gains, according to Microsoft; a "large wireless communications company" enjoyed a 28 percent increase in clicks in the Bing era.

The steady drip-drip of data points regarding Bing's market share has been a bit over the top--Statscounter twice issued press releases based on day-to-day estimates of traffic--but it's pretty safe to say that the launch has gone well for Microsoft. How well? Data from companies like Compete and Hitwise point to only very small gains, according to Search Engine Land, which believes the real evidence of Bing's staying power will come once the summer vacation period ends and overall search queries rise.