DKIM becomes more official

> Forcing free provider users to send mail only from the free provider's
> systems would also increase the bandwidth and processing costs of the
> free provider.

It would, but that's exactly what gmail wants its users to do.  They 
provide POP, IMAP, and submit servers to anyone who signs up for an 
account.

Regards,
John Levine, johnl@iecc.com, Primary Perpetrator of "The Internet for Dummies",
Information Superhighwayman wanna-be, http://www.johnlevine.com, ex-Mayor
"More Wiener schnitzel, please", said Tom, revealingly.