The Hollywood Reporter printed an article stating the Cam has been cast in Twilight but no role was mentioned in the release, but we have it from what we believe to be a credible source that it is James. (the info is at the bottom of the article) He is probably best known for his role in The OC. Here is his IMDb page. As soon as we get more information on his role we will let you know.
EDITED: We now have it from a credible source that Cam will be James. Also, for everyone’s security, please no posting of phone numbers!!! We will delete them if we see them.
Incidentally since this will no doubt come up. Lomesir discovered that his last name is pronounced: Jhee-dant-ay