From the New York Times:
If you read the comments on our post asking who uses AOL, you would think that a big number of the company’s users simply keep their AOL.com e-mail address to hear from long-lost correspondents who haven’t heard they have moved on to Gmail.
I checked with comScore to see how they measure AOL’s audience, and the perception that Gmail is trouncing AOL mail simply isn’t true. Yahoo’s mail service is the king of the hill, towering over everyone else.
AOL’s e-mail seems to be a big and engaging service that is holding its own with users. Gmail, by contrast, is growing in the number of users, but is far behind the other big Web mail providers in how often users check their mail and how much time they spend on the site. That would imply that it is Gmail, far more than AOL, that is being used as the supplemental throwaway e-mail address.