On Leoville, Leo Laporte reports that:

"AOL is giving its seal of approval to a reworked Microsoft anti-spam proposal. The technology, known as Sender ID, was rejected by the IETF last month because it was encumbered by Microsoft patents. The patent has been restated but it’s not clear whether open source advocates will accept the new proposal."

"rejected by the IETF" is strange wording in this case.  The proposal was soundly rejected by the open source community who disagreed -- not with the technology -- but with the license that was needed in order to incorporate the technology into products.  That AOL has accepted the proposal is an important development because AOL is a major player in the anti-spam effort, it understands the real place of authenticated mail, and it must have worked with Redmond behind the scenes to try to reach a compromise that was impossible in the volunteer world of the IETF.