What's the deal with comment spammers and Google?

The past couple of weeks, I've noticed a growing number of attempted comment spams (both here at Fusion and at some blogs I run in my offhours) that include links to www.google.com. You'd almost think that whoever's doing this is hoping the spam will be caught and blocked - because the anti-spam software we use automatically adds links in spam messages to a blacklist. Hokay, but why? Anybody have any theories on why the little rodents either a) want to increase Google's PageRank in its index or b) want blogs to (inadvertently) block comments with links to Google? I can't figure it out. Back to Compendium