For a few days now, google supports a tag-attribute rel='nofollow'. Links with that attribute are not followed and not ranked by google anymore. Now, a whole lot of weblog authors hurry to rel="nofollow" enable their comment pages to make comment spamming useless. I thought about it. My conclusion is: 'To rel="nofollow" every comment is not desirable. Not at all.' Why? Because by following links google builds some kind of semantic web thingie. It puts your pages to a certain context by examing who links you and who is linked by your pages. Furthermore, links in comments and trackback are very often part of this link context. By disabling googles context finding capability you kill a strength of weblogs. Maybe you kill 'the strength' of weblogs.
Please, try not to use rel="nofollow". If comment spamming is really that awful in your comments, please check comments anyway. There might be links that you want to set rel="follow". By the way, I did not put any link to this post to give an example for what would happen if we all started using rel='nofollow'.
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