Still even yet MORE Batman Begins! (it's petering out now, tho)

From Pinoyexchange:

spiderdude: uh...the main reason Burton's batman was a big hit in the box office is because it was the 1st time we saw a batman movie...

Maybe because Burton also has (or had) the popular touch? He had two hits beforehand, Peewee's Big Adventure and Beetlejuice, so it isn't like he's a novice at making popular movies--or movies heavy with SFX.

And remember--batfans hated what they were hearing about Burton's movie; they hated Keaton, they hated it that Burton's never directed an action movie before...so the movie was a hit despite the many fans, and was an even bigger hit than the first real major superhero movie, Superman. So if Burton's work appeals to audiences far beyond worshippers of flying mammals like ourselves (besides looking like a genuine work of art), belatedly winning most batfans along the way, that's his accomplishment.

From Atlantic Refugees

JC: By the way, I didn't find Keaton's Batman to be colder or more distant than Bale's.  If anything, I thought he seemed too warm and approachable...too emotionally well-adjusted and passive to actually feel compelled to dress up as a bat and play vigilante.  He also wasn't even remotely believable as an action hero...we had to suspend our disbelief in assuming that the suit was doing most of the work.  He wouldn't survive an encounter with multiple thugs attacking from all sides, which is why they only ever attacked one at a time (how convenient). 

Why, Keaton is the least likely example I can think of of the typical action hero and that's why batfans were so hostile to the announcement that he was to play Batman, and why he holds so much appeal to me, even now; he's constantly surprising you. Bale--well, I've seen him buff up in several films, including American Psycho, so hearing he's going to play a semipsychotic action hero isn't exactly something that would make you sit up and take notice...

One thing interesting about Keaton that hints at his being suited to play superhero, or at least a costumed hero: in all his performances, even the comedies, his reactions are razor fast and unpredictable; that's the unique advantage of being a comic actor (timing is everything in comedy; surprise too). You can believe he'll respond swiftly to an attack, and you can believe you're never know what the response will be, exactly.