Brosnan should come back for one more.
Although I disliked him at first, I think that he is the best Bond.
(And this in a time when the Bond films are imo the worst ever.)
The rumor mill on this is always moving, mostly fueled by the Bond-hopeful's agents and reps. I remember reading that Broccoli herself meets and approves the choice... So the rumour mill is purely to try and get faces in front of her and her people by candidates that are apparentley not close enough to her.