Ummm...

While the supposed casting for a Hitch-Hiker's film revealed in this article is pretty good, somehow I'm doubtful that Freeman and Nighy's parts in the movie, should it actually happen, are cast in stone.

It's just that, with a director not assigned to the project yet, I'd say that all castings would be pretty tentative, given that the director is likely to have hs own ideas on who he might want to have in the role. As neither Nighy nor Freeman are (yet) the sort of actors who can get directors hired or fired on a project, one wonders whether 'tentatively offered the part, based on directorial approval, timing, and other commitments' has been replaced by 'cast as' for the better publicity it might bring?