Hashcash does indeed aim to prevent it. If you don't provide a valid hash, your message is rejected. nofollow tries to work around an accept-by-default policy.

Yes, people who use Google may reap some benefit — at least, they might once the amount of abandoned but commentable blogs has sunk enough that nofollow actually makes a difference. Make no mistake, we're talking about a pretty large time scale here.

Comment spam is not useful solely because it influences rankings. Does anyone rank anything based on the content of your inbox? Yet email is flooded with spam. Sure, the fact that comment spam can be used to game search engines is a nice bonus and currently an important reason to deploy it, but if that incentive disappears, comment spam will nofollow into demise. It's here to stay.

The bottom line is: nofollow does not benefit a blog owner. Unlike other options which do. So by and large, nofollow is irrelevant on the spam front. It is only going to change the way the web works outside of spam: like the horde of bloggers who rejoiced that now they can link to the people they're deriding without improving the linkee's ranking. Sigh.

Makeshifts last the longest.

In reply to Re^6: (OT) nofollow considered harmful by Aristotle
in thread CPAN::Forum opens its virtual doors by szabgab

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