I like Batman Begins
a lot, but Katie Holmes' performance is worth more than a small demerit in my book, and the idiotic science of the microwave generator/fear drug shouldn't have made it to screen. Apparently, it activates when water is vaporized, but no one was ever affected by taking a hot shower. And, of course, the microwave generator vaporizes water -- just not water in people's bodies, it seems.
The Dark Knight
, in my recollection, replaces Katie Holmes with a better actress, but doesn't give her as much to do (and then kills the character). It also struggles to make Two-Face work, both in terms of realism and character motivation. Then, there's the Joker's schemes; Heath Ledger is magnetic, and his performance does well to distract from the twisted plot machinations, but his plans don't always make sense and often rely on our heroes lacking intelligence.
Which is not to say I dislike either film; the first one is excellent and the second nearly as good. It's a testament to their craft that The Dark Knight Rises
is the only superhero movie that I've been anticipating in several years. I'm rather tired of the genre and don't expect to be looking forward to another superhero film anytime soon, unless someone finally does the Hulk justice (unlikely, given the tepid reception of the Ed Norton version, which got it mostly right, but was hurt in editing).