First of all, and this probably won't come as a shock to those who saw Star Trek Into Darkness, but Cumberbatch is being eyed to play a villain. Or perhaps THE villain, "almost certainly a Sith" they say, who will appear throughout the trilogy. So that's multiple films, meaning he won't be some flash in the pan Darth Maul-type. He's going to be a fixture, perhaps on the scale of a Darth Vader.
Next is that Cumberbatch may have to drop more than just Guillermo Del Toro's Crimson Peak if the deal is going to come together. It's not exactly clear what films those would be, but a likely candidate would be long-developing biopic The Imitation Game, where he would have played Alan Turing.
As expected, Cumberbatch's involvement has been denied through official channels, but at this point why should we believe them? This is a JJ Abrams production, after all, and he's never been one to shoot straight. In particular he's strung us along in regards to Cumberbatch when it came to his Star Trek role.
An announcement is expected from Lucasfilm soon that should include this news and perhaps something more, so we'll just have to wait and see how it all shakes out. Star Wars: Episode VII begins filming early next year for release in 2015.
