But not really. Linking to an article to discuss it is not copyright infringement. And therefore they would have no legal right to tell you what to do.

I suppose they could have all their licensees check Referrer headers and reject hits for unapproved sources, if they were serious about this... but I can't imagine why anyone would go along with that. And it doesn't change the fact that posting content on the Internet and asking people not to link to it, will never really be a good plan.