We recently analyzed all outgoing email traffic from the MailChimp servers to see who the major email providers are, and to identify trends (analyzing gobs of email data is what we do in our pastime here). So we though we’d share our findings:

Major email domain market share

Yahoo and Hotmail are tops, but Gmail is on an upward trend (related study: Gmail Users More Engaged?). AOL has some work to do, and Comcast is pretty flat.

BTW, if you like email marketing stats, or need data to print and show to your clueless boss, bookmark MailChimpCharts and EmailStatCenter.