] Comcast, the country's largest provider of high-speed
] Internet access, has begun blocking a channel frequently
] exploited by spammers to send out large volumes of
] e-mail, a move that many technologists say was long
] overdue and should be matched by other service providers.

This is not good news. Blocking all traffic with a destination port of 25 ties all email service to the ISP. That's corporate and hosted email servers also. This will cause problems with people who move between networks often. It also makes it easier to monitor email sending.. Its a bad precedent to allow ISPs to block the ability to use services at the network level.

An Internet connection should be a full Internet connection, not one that only allows you to send traffic on certain ports. This is a bad idea in disguise as a good way to stop spam.

Its email that needs to change, not the Internet. The Internet should remain stupid, and treat all ports as equal. It should not have ridged rules imposed upon what can flow over it because of a problem with an application. Taking away user's ability to contact external SMTP server's is a big thing to do for a 20% reduction in spam, which the spammers will adapt to..

Comcast to Firewall Port 25