The Hollywood Reporter states that Chris Cooper has signed on to play Norman Osborn in the sequel. Osborn is the billionaire scientist and industrialist who eventually becomes the villain known as Green Goblin.
The only appearance the character made in the first film was in a piece of window box advertising for Oscorp. The role was originated by Willem DaFoe in Spider-Man. Dale DeHaan has been cast as his son, Harry, a role originated by James Franco in the previous franchise.
Cooper is a skilled actor, and a great choice for the role. But one has to ask when will it be too much? There are a lot of characters in the film, many of whom are villains, which need screen time to develop. Whenever you try to cram this many characters in, you end up losing something in the end.