Talent must count for something here....
im gonna say brad pitt.
Would you consider tom hanks a "movie star"?
^^Yes, Tom Hanks 'is' a movie star, mainly because he stars in movies.
In my opinion when you are judging people of any occupation, including 'movie stars', then you should judge them based on how well they do their job....their level of talent, not how famous they are, or how rich.
I think that the hallmark of what makes a great actor, is the ability to play a role of a person who has a completely different personality from your own. In other words, I dont really see Brad Pitt, Tom Cruise or definitely George Clooney as being great actors, because most if not all their roles are personalities very similar to their own. They all usually play characters who are "hip", "cool", "good looking", etc. They are basically just playing themselves.
One of the best acting jobs I've seen was involving Charlize Theron in the 2003 movie 'Monster', where she played serial killer Eileen Wournos. Eileen Wournos was an unstable, depressed, bi-polar, schizophrenic 'Tom-boy' type woman who looked and acted VERY rough. Charlize Theron in real life is a pretty, glamorous, soft spoken, feminine woman. However, she was able to convincingly play the role of Eileen Wournos to a tee. I believe she won awards for her acting in that movie.
I wouldnt say that Charlize Theron is my absolute favorite actor/actress, but she did a damn good job there! I'd agree that Paul Newman was good, so is Robert Duvall.