Changing the Net to combat spam

Reflecting on two changes in web architecture to combat spam.
* LOAF is a new proposal for social spam filtering.
* AOL has been quietly blocking the websites of spammers
I ought to like the first (which uses a social network) and dislike the second (which relies on a centralized power). But my reaction is the other way around.
The blocking of spammers sites makes me want to cheer. This uses an age-old technique of punishing the anti-social with ostracism. The problem with blacklisting in general is lack of accountability. In order for the system to be fair, AOL should provide a test site for users to determine if the sites are being blocked, and there should be a public appeals process where people could get their cases reviewed and decided.
On the other hand, the blocking or slowing of all emails from strangers makes me sad. One of the beauties of the internet is the ability to meet new people with common interests. The restriction of social networks to people already in one’s social circle contradicts a core value of the net. This solution would take us back to the bad old world where you needed to know someone to get an introduction. The LinkedIn model becomes mandatory, not optional.
Blocking email from new people would seem to punish the innocent much more than blocking the websites of spammers. Mail from innocent new people will languish and die in the company of viagra ads. The senders will never know.
By contrast, if the spammer blacklist had diagnostic and appeals, the innocent could free themselves from the blacklist. The guilty would be ostracized, and the innocent could speak freely.
I’d love comments from sensible readers.