Other than how they chose to deploy the notice late on a Friday, I have little problem with this.
Reviews should be about the book and not rants about the author personally.
As long as this doesn't extend into the discussion areas, I'm fine with it. And it doesn't seem to, as this thread :
http://www.goodreads.com/topic/show/1403751 is alive and well at the moment.
Hopefully, this will cut down on the lesser rants as well as the more extreme fan/author vs. anti-fan issues that have been going on there for over a year.