GOOGLE -- High level talks have sorted out a way for blog publishing routines to incorporate the "nofollow" attribute. So comment spammers would end up with the rel="nofollow" in the syntax of links they make on trackbacks or comments. Typepad has been doing something like this for several months. In fact, Typepad will stop-cock comments before posting them if they come from a known spammer IP.
Google's publicity campaign about the "nofollow" tag is most welcome. And in all things Google, some people have seen the revenue stream on all this. Russ Beattie is removing the "nofollow" tags when people pay him a dollar to keep a straight outbound link.
There was a time when I was battling comment spammers on a daily basis. Thanfully, Typepad takes care of my problems at a server-side level.
- Round 8 (December 2004): I note I've run for more than three months without clearing spammers from my comments.
- Round 7 (August 2004): "I attract fewer than 10 comment spammers a week" while serving 1000 HTML pages a day.