It seems that not only is Johnny Depp fine with the idea of doing more Pirates movies on down the line if the script is right, but so is Verbinski. So basically, a Pirates of the Caribbean 4 is pretty much guaranteed. That said, I wouldn't expect it to happen for quite awhile. Personally, as long as the main talent in front and behind the camera returns and the screenplays are just as good, I see no reason why they shouldn't continue the franchise off and on throughout the years.