I believe that there is a fine balence between the author's actual boook, and his/her PR. Many books are great, and many people will read them, but having a good PR will no doubt help the book, but I believe that if the story is a good one, it will gain it's deserved recognition.
When comparing today's writing with that of Charles Dickons, you hacve to remember that the was over a hundred years ago, and people didn't have the technolagy to kep tham busy, as they did now. So really, it is a combantion.