Technorati: Search for google nofollow

There's a lot of comment and speculation about the possible Google's comment spam solution, if indeed that's their solution. I'll implement it on my hosted blogs—of course, and it'll be transparent to the user.

However, I wonder at it's effectiveness. Sure, it takes the incentive away, but will this be enough to stop comment spam? There's the point about getting other search engines to do the same, getting all blog technologies and individual blogs to incorporate the feature... Maybe the incentive to comment spam will disappear over time? I wonder how long that will be.

My problem, currently, is with referer spam, though we tell Google not to look at the referer page, still they spam. Their reason, "if I spam a million sites a day, and a handful of links actually increase my Google Page Rank, that has to be worth it, since it cost next to nothing to do, and pays in better search listings."