But this does not prevent comment spam it only makes it distasteful for the spammers. Google will not follow those links that are posted with this attribute but they still appear on the site. I think deleting or banning the commentor alltogether is a better solution. Nothing can replace a good site admin. Geeklog has a plugin call SpamX that allows you to ban comments with specific URLS or language in them. This in combo with an aware admin is the best defence.
But this does not prevent comment spam it only makes it distasteful for the spammers. Google will not follow those links that are posted with this attribute but they still appear on the site. I think deleting or banning the commentor alltogether is a better solution. Nothing can replace a good site admin. Geeklog has a plugin call SpamX that allows you to ban comments with specific URLS or language in them. This in combo with an aware admin is the best defence.