I have to think it did personally. I mean I can't imagine that Batman and Heath Ledger, on their own, suddenly and magically became a $1 Billion entity on their own merits.
The first Batman movie from 1989 made about $500 million domestically when you adjust for inflation, and then another $160 million international unadjusted (which is probably at least $300+ million adjusted). So, that's around $800 million adjusted.
Yes, that was then though. The previous film, Batman Begins, made $372 Million worldwide three years earlier in 2005. The movies Heath Ledger starred in weren't exactly "tearing it up" at the box office either, which is no fault of his of course. So was it just a coincidental sudden interest in Heath Ledger and a sudden rejuvenation in the Batman saga that made TDK successful? Sorry, I can't buy that at all.
Honestly, I think he is a fine actor and all. But he sadly dies, and here comes the media, and ultimately the publicity for the movie, as morose as that may sound. The media became infatuated with Heath which indirectly gave the film, a film that likely would be high profile fare none the less, a hell of a lot more exposure.
. They are calling it the next 2001. I have seen the trailer and its looks good.
