I think this is an excellent idea. It has troubled me that the only discussion of the actual movie has been scattered among the updates about how well it's doing.
I'm wondering if it would make sense to have more than one Watching Project topic for the movie - for example, one for the part that takes place during Barnabas's lifetime, one for the part in the 1970s before he is released, and so on. It might lead to some confusion, but there's lots to say on various subjects within the movie.