I honestly don't know what everyone is expecting. Casting was big news on Batman Begins because it was the first movie..all these roles were being filled for the first time, and all by very big stars.
We've already had the most newsworthy announcement we could expect concerning this production, the casting of Joker. The only other major news we were waiting for was the casting of Dent. I honestly didn't expect to hear much more, with the exception of whatever new characters Nolan's adding to TDK.
When a new Spider-Man movie goes into production, I don't expect to hear reports about J.K. Simmons or Rosemary Harris returning. I assume they are, unless I hear otherwise.
That's what I'm assuming with the cast of Batman, unless I hear otherwise. In the case of Katie Holmes, we heard otherwise. And it's that deviation that makes it newsworthy; also the fact that she's Mrs. Tom Cruise and one of the most heavily spotlighted figures in Hollywood in the last year.
If this was a Fox production with some hack at the helm, I might be more inclined to worry. But this is the Nolan. Let him work his magic. He'll get it done.