Re: How do we avoid the third act curse?
Look at Die Hard 3, The Good, The Bad and The Ugly, Return of the King, Last Crusade. etc.
1. They don't reuse the same plot as the original.
2. The studios didn't screw around with the director and writers ideas.
3. They kept the same tone and style as the originals. I.E. no shark jumping.
4. The filmmakers listened to criticisms of the original films.
5. The action was consistent with the others.
6. None where rushed to meet a release date.
As far as I'm concerned Nolan is the kind of guy that would adhere to all of those (Except for 4, somebody get Bale some throat medication please).
Bring on Batfleck, Wonder Gal and EisenLuthor!