There is an amazing scene in Gotham Central where one of the detectives is talking to who he thinks is his lieutenant about a case. It is later revealed that was actually Batman. Now that is something I would love to see in a live action show.
I could also see the show hyping around the police of Gotham and since Gotham is typically associated with Batman many people would be drawn in just to see what it was about. Also you might want to add some flashy villains in the preview along with maybe some poster that looked like.