Great Google into one more step about changing their SEO policies by treating nofollow links in a different way. Google will send nofollow PR juice to thrash bins and no one will be affected with nofollow links. Normal links will get less PR juice due to the existence of nofollow links.
Do you approve comments from names which include keywords? Should we approve it or not? Here is what you can do if you are in a confusion about approving a comment from keyword spammers or deleting it. Read the article on what kind of commentators are safe to be approved and who are the ones which require a kick out of your comment section.