Trust me if you recast in SM4 the franchise will be written off. Before anyone mentions Rachel Dawes, no one really liked her (and yes the mainstream liked MJ in the first two movies, because they never read the comics) and it a recast after only one movie. This maintains credibility for the franchise.
I hope he is wrong about the marriage, I think SM4 should be the last one. Get them married at the end, end the franchise right and then wait a decade and reboot.
As for the villain, glad to hear it is not a vampire. Raimi yanking fans' chains, what a surprise.
I'm hoping Lizard...a giant monster in the sewers that tears crap up like subways and stuff? Sounds like NYC in movies.