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Google’s email service finally became the world’s largest email provider this month, according to ComScore. Gmail had claimed the top spot for itself this summer when it announced 425 million monthly active users. However, VentureBeat at the time pointed out that these numbers wildly differed (by 136 million) from those of ComScore, which tracks home and work usage but not mobile. Hotmail and Yahoo Mail self-report, too, but their numbers were much closer to ComScore’s.

According to October ComScore data, the number of unique visitors to these email providers is down overall — perhaps because of the recent introduction of Microsoft’s Outlook and AOL’s Alto — but for the first time Gmail is in the lead.

Around the world, Yahoo and Gmail are competing for similar markets, with both companies counting their highest number of unique visitors in the United States, Japan, India, United Kingdom and France. Hotmail seems to have a slightly different market: Its highest number of unique visitors are not only from the United States, United Kingdom and France, but also Brazil and Mexico.

Despite Gmail’s worldwide dominance, third-place Yahoo owns the U.S. market, with 7 million more unique visitors than Gmail as well as a higher penetration. That means 40.8 percent of online Americans use Yahoo, compared to 36.7% using Gmail and 18.9% using Hotmail.