This could be interesting. Although I think it would have been a lot more interesting if they had just done a Gotham Central adaptation. That way they could have already had all of the villains active, and would be able to drop the occasional reference to Batman.
My only issue with this that if they want to have the familiar villains then they will have the cops dealing with them before Batman was around. I was under the impression that Batman's excitance was part of what drew all of the super villains out. And like someone else said up thread, doesn't it make Batman a little unnecissary if the cops had already been dealing with the villains for years.
Now if this was in an alternate version of Gotham where Batman never exists, but all of his villains still do, that could be interesting.
Having said that, I admit I'm still