I just saw it again and I'm afraid that it really is just not a very good ending to the trilogy. I mean, it works well enough in a sort of self-contained summer blockbuster comic book sort of way, but the leaps of logic required to sustain the suspension of disbelief seemed more glaring this time around. And its biggest flaw is how it wraps up the whole story.
Mostly what's bugging me is the whole general direction the thing went after TDK. I feel like the story had some pretty tortured convolutions in order to accommodate a few key ideas that the filmmakers obviously wanted to get into place - the biggest being that Bruce retires (twice). I've said before that I think the retired badass coming back is a rather tired trope and it was here as much as anywhere else. The sad part is, it just didn't have to go that way. The story could have easily continued with Batman an outlaw vigilante, which is where I felt like the ending of TDK was headed - and I thought it had all sorts of intriguing possibilities for Bruce's journey and his relationship with Jim Gordon.
If they just had to continue with the Harvey Dent, martyred savior of the city tale - which always felt a little far-fetched because Dent wasn't exactly shown to be MLK or anything - it could have gone the way of a law passed which "gave law enforcement teeth", leading to the corruption of power in Gotham. That is, instead of the bizarro unjustified people's revolution we got, the story could have gone more to power structures out of control - a clean city, but at the price of freedom. Batman stories tend to work best in a highly corrupt world so I'm sort of astonished that this story possibility was passed up in favor of a Red October scenario.
You want Bane in this story? He's a terrorist run by someone who seems a legitimate leader of power (Miranda Tate), to keep the people frightened so that tight laws can be kept in place. Her secret plan is to destroy the city? Then she unleashes Bane, whose activities lead to even stronger laws going into place, special vicious police teams being set up rounding up everyone in sight - this gives plenty of opportunity for action and fisticuffs as Batman has to battle these forces of tyranny, and in the end Miranda says, hey, I'm Talia - I've been wearing you down to take my revenge and now I'm going to blow up the city you've been working so hard to save.
What it probably doesn't allow for is 1) Bane breaking Batman (which would have been no tragedy to me - I thought the whole Knightfall/ Death of Superman/ Artemis replacing Diana extravaganza was a bunch of stunt story-telling when DC went after it in the first place) or 2) Bruce happily retiring at the end of the story. Now, in theory I don't mind Bruce retiring except that this story seemed to want to predicate it on the idea that Gotham was fundamentally changed as a result of Bruce's activities as Batman. And I just don't feel like this was established in the course of the trilogy. The whole Gotham sucks because it's a mob-rub town never quite played out convincingly for me, so it is equally hard for me to buy that Gotham is now a-okay because the mob got put away. I think the overall story ends up feeling very simplistic for asking you to accept that premise in order to have it end happily.
Which brings me back to my original point - TDKR seems to have been written this way: we want to have Bruce retired, and he comes back to fight Bane who breaks him so he can return (again, as someone else pointed out), and Bruce retires (again) but this time for good and with a sexy companion. Now how can we make that happen? Instead of saying - here's the ending of TDK, what happens next? and then figuring out what compelling things might come out of that they had to twist and turn to work around some beginning assumptions about what the story just had to include. When really, it didn't have to include those things at all.
In the end, it just didn't feel like what was really engaging about the the trilogy - Bruce Wayne's journey from revenge-driven youth to idealistic, ambitious vigilante to discredited hero - was played out in a compelling way. TDKR starts with Bruce essentially having failed (Gotham's clean but it's all based on a lie) and ends with him stopping the destruction of the city and retiring but it didn't feel like his goals were fulfilled. It seems like the point of the story is that his goals change, but, if so, there wasn't enough character development for him in TDKR to make that feel like a particularly compelling story.
All that said, there are some really nice moments in the movie. Selina Kyle is really fun - so much so that she pretty much upstages Batman. And I have to give it to Christian Bale for the first fight scene with Bane - he does a really tremendous job of bringing intensity to that scene. You can feel how hard he's having to work for every blow, how frustrated he is at his loss of physical prowess, how much the whole thing hurts. In general the performances are great, and the very, very end, with Blake in the cave did work quite well.
But, a great story has to have a great ending. This one doesn't, unfortunately. It's hard to do with a superhero. B+ to the whole trilogy and E for effort - Nolan tried hard and succeeded about 75-80%.