Still thinking of little but Serenity

Link has spoilers - http://themagazine.millarworld.tv/index.php/?p=205

The cast of Firefly/Serenity played Catchphrase on the bus on the way out to the location on their first day of shooting the movie. I find that so very endearing.

Now, can anyone give me the straight dope on which actors are signed to a three-picture deal and which aren't?