For the past two weeks, the market share of US Internet visits to Gmail has been higher than visits to YouTube. Previously, YouTube consistently ranked 10th among all websites by market share of visits until the week ending Jan. 10, 2009, where Gmail moved up one rank to reach #10. The websites have been swapping positions regularly ever since.

Among a custom category of all Google properties, Gmail ranked 2nd behind Google for the week ending Mar. 7th, 2009.

Both websites are receiving more visits than one year ago, with a bigger increase in the growth of visits to Gmail. The market share of visits to Gmail has increased 70% for the week ending March 7, 2009 as compared to the same week last year. Visits to YouTube also increased 16% during the same time frame.

Gmail’s top 3 sources of traffic were Google, Facebook, and Yahoo! Mail, totaling 58% in February 2009. Google accounts for the largest share of upstream traffic at 49%, which has increased 10% from February of last year. Facebook represents just over 4% of the upstream traffic and this share has nearly doubled when compared to the previous year. The third source of traffic, Yahoo! Mail, presumably from Internet users with multiple web-based email accounts, sent fewer referrals in Feb 2009 and the share declined 18%.

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