Media Post has more details on Time Warner's CEO Richard Parsons commenting about AOL nearing the one billion dollar mark in ad revenue.
[Mike] Kelly [president of AOL Media Networks] says the AOL division's revenues are derived from a combination of cost-per-click (CPC), pay-for-performance, and brand advertising, as well as revenues from AOL Europe. One-third of AOL's advertising revenue comes from search revenue via the company's relationship with Google, and through direct search from AOL, according to Kelly. That percentage is expected to grow, although it was unclear by how much.
Lots more numbers in the article.