There are Updates threads in the Producton session, actually, where people talk about what they're working on and post some frames of what they've done so far. There's also the "Frame From Your Upcoming Film" thread where...well, the title says it all.
As for the casting call, there's the audio section.
And, if you're searching for ideas, there's a sticky thread in the Pre-Production section called "Post your ideas" where people can post something they came up with and someone else can borrow some of those stories, if the creator is ok with it.
Those threads can contain more information than what one could possibly post here. If someone wants to know about an update for a movie he just looks the last post in that thread, in this thread filled with tons of updates of different projects he should look for it, and it would not result easy to find it.
I'm sorry to say this, but this thread isn't really useful.