io error has write a long and interesting article – “Nofollow revisited” – taking a look at the affect nofollow has had on the web since google introduced it about 4 months ago. The article contains some very interesting points and I have to agree with him in the fact implementing nofollow has had no real effect on the amount of comment spam attempts received on this site – the most sure fire way to reduce comment spam attempts seems to be to not post – every time I get round to making a new post a new set of attempts start to flood in a few hours later!
So far I have resisted using a nonofollow plugin on my site – mainly because I don’t exactly get that many comments and so I doubt I would be sharing much google juice – however this site does have a PageRank of 5 so I must be doing something right!
In general I have found that the combination of BadBehaviour and Spam Karma 2 keeps my site free of all but the most determined comment spammers – I think it may be time to abandon nofollow.