I am going to second this idea. Having multiple authors for our blog posts is going to be a must for a few clients as we move into the future. We have many clients in the your money your life category where this is currently becoming problematic. We would like to be able to add multiple authors to the content with different associations to the content. So we would have an Author, Reviewer, and fact-checker for the specific articles.
Investopedia is currently doing this on their site.