Google Maps has overtaken AOL’s MapQuest in terms of unique visitors— with 42.2 million monthly uniques in January, to MapQuest’s 41.5 million—according to the latest stats from comScore. It’s the first time Google (NSDQ: GOOG) Maps has attracted more traffic than MapQuest, though there have been signs that the milestone was around the bend:

—Google’s grabbing marketshare, too: Last week, Hitwise analyst Heather Hopkins noted that Google Maps was catching up to MapQuest in terms of market share—a different benchmark, but still a viable indicator of scale. MapQuest’s lead over Google Maps had slipped to just 1.6 percent in the first week of January. That trend didn’t hold, as MapQuest regained an 11 percent lead four weeks later, but it’s still down significantly from a year ago, when Hitwise data showed that MapQuest owned about 50 percent of the market to Google’s 22 percent. Since then, MapQuest’s share has plummeted to 39 percent and Google’s hovers at about 35 percent. And while sources tell SEL’s Greg Sterling that MapQuest still trumps Google Maps in terms of time spent on site (i.e. user engagement), the fact that Google Maps is now attracting more unique visitors (which is likely to continue) is worth noting.

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