It was an ending that tied things up (Alfred seeing Bruce and Selina together) and left things open for a future franchise (Blake entering the Batcave).
So on one hand it has a Return of the Jedi feel to it, i.e ending off the series with Alfred's wish of seeing Bruce with a family (albeit, was just Selina) coming true and tying things up, but on the other hand, leaves things open for a follow up (kind of like the first Matrix film) with Blake discovering the cave.
I think Nolan gave it the ending he did, because it was his end to his trilogy, and maybe he wanted to give closure to the audience on the outcome of Batman.
The whole thing about Batman surviving the blast, it's a film and I'm not too worried about the logistics of it all. We don't know when he ejected exactly. We did see Batman piloting the Bat with some time left, but not in the same shot...so the shot of Batman could have been when he was ejecting powerfully away...
Most people know Batman's sidekick is called Robin, a lot less would kow it's Dick Grayson, hence why I think they went down the route of using the name Robin.
What I want to know is:
- How did Blake find his way to the cave? Who put that stuff into his bag?
- Is he now just going to be a glorified babysitter looking after all the kids at Wayne Manor?
Good film, not as good as The Dark Knight, but a good film. A bit like Empire and Jedi really...Empire is a better film, but Jedi ends the trilogy off nicely.