In the month of December, Bing, the search engine Microsoft has been working hard (and spending like crazy) to turn into a serious Google competitor, officially became the second most popular search engine online, according to ComScore.

Bing, which was launched in 2009, cracked 15 percent of the search engine market share last month. Yahoo!, bumped to third place, had 14.5 percent.

With Google's recent, controversial decision to prioritize links to its own Google+ social network in search results, competition between the juggernaut and Bing is starting to heat up. Yesterday, Gizmodo's Matt Honan wrote a much-cited post declaring that he's abandoned the Goog for Microsoft's greener pastures.

Second place is still quite a long ways from first, however. Google is still the runaway leader in the category with nearly 66 percent of Internet searches.

[Comscore via AllThingsD]