[jcc80]

How can this be enforced? Will Google determine when the author meta data is different for a blog and not pass page rank for those posts? Blog owners would just react by making the post under their default account. Isn't the real issue the quality of content, not who's writing it? It just seems odd to hear that Google is going to go after guest posts instead of focusing on the content.

[the_watcher]

It's easier to go after authors. My (possibly naive) hope is that they are working really hard on evaluating content (Arguably G+'s social signals are the most important input for this), and they'll move towards that as they improve. High quality guest blogging is fantastic, and it would be sad to see it vanish because of this.