(p.s. from some of the descriptions of the specific cartoons on the news I'm not sure if they are actually on that page. Has anyone actually seen these cartoons?)
Micropayments, fungible (cash) or otherwise (hashcash), have been suggested sa the solution to spam for a long time. Clearly it's a very tough deployment problem (you need lots of people to suddenly start using it), but it would appear that Goodmail have persuaded AOL and Yahoo to sign up (thus might have solved the deployment problem).
The hope is that, by increasing the cost of sending email, one can make spam uneconomic. But it really doesn't appear that Goodmail is even trying to do that; unpaid email is treated the same as it always was. If the price is too high for spammers (and the quoted 1/4 cent probably is) then they won't pay and spam will be exactly the same as ever.
As an email sender, the only reason I would wish to pay this is because I have good reason for sending the email (ecommerce confirmations etc) and I don't want the hassel of dealing with customers who's spam filters eat my emails. That's pretty weak. These people have had to deal with it for a long time and rarely can customers not dig through their filters to find an email that they're expecting.
And since Goodmail are getting paid for each email, their motivation for not accepting emails from spammy senders isn't perfectly aligned with the interests of their customers. Clearly they don't want to squander any trust - but there's a strong temptation to see how far you can push customers for that extra bit of income.
And is spam really a problem for anyone these days? I get about 200/day and > 95% fall into the spam trap with very few false positives (that's with Gmail). The spams which do get through are random assortments of words usually.
So I predict that Goodmail will get few customers and make very little difference to anyone.
(and clueless quote from that article: "I still gets e-mails from lists I signed up for three years ago, but I haven't responded to a single one." - then unsubscribe you moron!