The interesting thing about the shows that have completed scripts is that even those shows may not be able to continue production, because the show runners (often writers themselves) are picketing!
I'm not sure if the writers have exclusivity clauses in their contracts, and I'm not sure about union requirements, either. I'm assuming all writers are in the Guild, but I could be wrong.
I love that the cast of The Office decided to support the writers by not showing up to work, and that people like Conan and Jon Stewart are keeping their shows dark. I definitely agree that Ellen should have stayed on the other side of the picket line to support her writers.
The writers are the backbone of the television industry. As much as it pains me to know that Heroes will likely come to an early end this season, the reason is very worthwhile, and I support it!