Today comScore reported January search share figures for the US market. We restrained ourselves this month, not posting on this subject before the official release, given the error that happened last time through one of the financial analyst firms and their early release of the data.

Google gained share vs. last month. However, the big news is that Bing is now firmly ahead of Yahoo in “explicit core search.” But using comScore’s expanded “total core search” definition Yahoo remains ahead of Bing.

Below are the official numbers; first explicit core search (no slideshows) and then total core search (including so-called “contextual search”):

Yahoo and Bing have now effectively changed places. Bing has taken share from Yahoo, while Google has been largely unaffected. Accordingly, the “search alliance” share of queries remains essentially flat at 29 percent.