My gripe with Ron is similar to Gundark's, I dont think he very inventive. Thats not to say that he hasnt directed some great films. A Beautiful Mind was alright I think, but hardly worthy of all the acclaim. I think he has gotten somewhat formulaic, and most of his movies are made to appeal to the mainstream (and why not, its a business) but this makes them sort of stale, IMO.
If he stays close to the book, this wont really come into play. But if they start taking creative liberties with the adaptation, Im sure it will go downhill.