"It's a huge coup to have Brad joining the cast. He has worked for Guy before and said if he could, he would do anything to help out" a source told the mirror.UPDATE: Usmagazine have a statement from Warner Bros. stating that Brad Pitt has not joined the cast, a rep had this to say:
"It was an oversight in the film not to make a bigger deal about Moriarty. He is mentioned as Holmes' arch enemy, but the bosses wanted Guy to make more of him."
"Jude Law [who plays Dr Watson] and Robert Downey Jr [Holmes] have already shot their scenes. But now that 10 extra days have been added to shoot the new ones, they may be called back for a day or two."
"It's going to be a full-on couple of days, but now the release date has been pushed back they might just do it in time."
"The report in today’s London Mirror is completely inaccurate. Brad Pitt is not joining the cast of Sherlock Holmes and we're extremely pleased with the production of the film. As planned, it will be released on Christmas Day, 2009. In order to complete the movie, we've scheduled a few days on set to shoot a couple of additional scenes, obtain pick-up shots, and perfect some of the visual effects elements, all of which is standard filmmaking practice."