Well, many members of AFTRA are also members of SAG, and this sends a message that they don't want a strike to happen. It is well known an Actors Strike would cripple the film and television industry, almost completely, except for select deals SAG made with independent film producers.
The Writers' Strike cost Hollywood $2 billion, so it's clear an Actors' Strike would cost double or triple that number. Some shows and movies were still in production during the Writers' Strike, but that's not the case with a potential Actors' Strike: Hollywood would be effectively shut down.
SAG is now feeling the pressure to sit back down with the AMPTP and get a deal resolved as quickly as possible, and I can assure you the studios and producers are feeling that pressure too. Again, a strike will hurt everyone involved. It is being reported that SAG may sign the deal with the AMPTP by end of business todahy (July 10, 2008).
We'll have another update when and if SAG and the AMPTP come to an agreement.
Source: Ain't It Cool News