Google overtook RIM and Apple in January, capturing the top spot for mobile operating system market share.

[ad#Google Adsense 300×250 in story]According to a new report released on Monday by comScore, Google’s market share rose from 23.5 percent in October 2010 to 31.2 percent in January 2011. That’s a 7.7 percent gain and enough to catapult the company ahead of both Apple and RIM.

RIM, who is now in second place, saw it’s market share drop 5.4 percent from 35.8 percent to 30.4 percent. Apple’s market share rose slightly from 24.6 percent to 24.7 percent over the same period.

The list also included Microsoft with 8 percent and Palm with 3.2 percent market share, respectively.

In the handset market, Samsung topped the list with 24.9 percent market share, followed by LG with 20.8 percent share and Motorola with 16.5 percent share. RIM with 8.6 percent share and Apple with 7 percent market share round out the list.