Ben Hammersley reckons Google’s rel=”nofollow” thingie is a bad thing and won’t work anyway. I’m not sure I agree, at least not with the economics part. email spam is hard to discourage because it continues to produce the desired effect (clicks) in a cost-effective way despite pathetic response rates and increasingly effective filters. rel=”nofollow” will kill comment spam (if widely adopted) because, in principle at least, there will be no point at all spamming blogs with links to your poker site once those links no longer boost Google pagerank.
Spammers may not be the kind of people you want in your hot tub but they are goal-oriented economic actors and they won’t waste any time at all running comment scripts once they realise they are 100% useless. Having said that, I’m sympathetic to Ben’s (and other people’s) concerns about the potential damage to the semantic (and social) web that a new class of weighting for links might cause. We’ll have to keep an eye on this one.
In the meantime, I’m sticking with a combination of MT-Blacklist, which works if you keep the blacklist up-to-date, and new kid MTCloseComments, which does something I’ve been whinging about for ages – it just closes comments once they’re a certain age. Of course, MTCloseComments might also contain the seeds of the web’s slow heat death but I can’t imagine how – the only people who post comments to old entries here are spammers (except this one).