Microsoft search share continues its slow upward crawl

The October comScore numbers are in and Microsoft has inched upward for another month with its Bing search engine.

In October, Bing reached 9.9 percent, in terms of percentage share of U.S. searches. Bing hit 9.4 percent in September, comScore's data indicates.

Bing's growth came at Yahoo's -- not Google's -- expense, however. According to comScore, Yahoo was down to 18.0 percent share in October, from 18.8 percent in September. Meanwhile, Google's U.S. search share rose to 65.4 in October,from 64.9 in September, based on comScore's data.

In October, Microsoft began rolling out a number of enhancements to Bing, culminating in a bigger "2.0" fall refresh last week. If Microsoft's search game plan is built on the idea of growing share substantially by combining forces with Yahoo, Yahoo's continuing share loss is looking less and less likely to shore up that plan.