To weigh in on the kid thing. My local cinema was packed with families for the Avengers. Young kids too.
I just don't see that with TDKR. I certainly won't be taking my girl to see it, I just don't think she'd find it enjoyable. She may even be bored for great amounts of it.
I'll sit down with her one day to watch Nolan's Batman trilogy, but not right now.
Also, despite the hype, TDK had about 20 folk for opening day at my local. Avengers packed it out.
TDKR will probably clean up, but I don't think it'll attract the same family audience. From the trailers Avengers looked fun. TDKR looks well crafted, but a bit dour. Presumably that's why they've thrown in a few jokes in the latest trailers.
But like John Snow, I know nothing