WebProNews

Sorry, Yahoo fans - September wasn't kind to your search engine of choice.  According to Compete's stats about market share and query volume, newcomer Bing did more than all right, though, which would seem to say some interesting things about the proposed Microsoft-Yahoo deal.

Yahoo's share dropped from 15.8 percent in August to 14.7 percent in September, which equals a month-over-month fall of 7.0 percent.  Meanwhile, query volume plummeted by a not-at-all-good 8.0 percent.

Bing's query volume increased by 8.2 percent during the same period.  Its market share eked up, too, from 8.7 percent to 8.8 percent. 

Obviously, Microsoft's incentive to forge a partnership will shrink if Bing can steal searchers away from Yahoo.  Yahoo might need to hold its own (or at least lose to Google, but not Bing) in order to make sure Microsoft doesn't think better of the arrangement before the 2010 target date.

As for old Google, it performed well in September and is still far ahead of its rivals, with Compete reporting that its market share increased from 72.3 to 72.6 percent month-over-month.  Only in terms of query volume did the search giant stumble, losing 0.6 percent.