Here's a good Q&A for the movie:
http://www.formula1.com/news/interviews/2011/8/12407.htmlRegarding the cast: The guy who played "Thor" in the recent comic book movie will play Hunt, and the guy who played the lead SS officer in "Inglorious Basterds" will play Lauda. Other people are listed, but I did not recognize them. I think the "Thor" guy could be made to look like Hunt. The "SS" guy I am not so sure about him looking at all like Lauda. Ron Howard does say that the screenplay is sort of centered on Lauda's comeback, so that might put bias into the film, which would not be as good as a well-balanced look at the two drivers.
One sad thing in the above interview: Ron Howard says that with today's tech, he doesn't need to actually film on location. He can do it all in the studio. The last thing I want to see is a bunch of bad racing-game CGI on the big screen. I want to see real (replica) 1970s F1 cars tearing up the real circuits, where-ever possible!

There is no replacement for that look and feel, IMO.