Captain Christopher Pike is central to the history of Star Trek. The first captain of the Enterprise, Pike was the predecessor to Captain Kirk, and even appeared in a few episodes of the original series. Now, that role has been cast in J.J. Abrams' Star Trek, according to rumor, and the person playing the part will be Josh Lucas, the star of Poseidon.
This production is really cooking now, although this is just a rumor. However, it comes from a source that has been dead on so far when it comes to casting rumors on the project, so you never know. Meanwhile, William Shatner has been on record as saying that he's not been contacted to be in the film, though Leonard Nimoy has, and that he's a little upset about it.