That's a fun guessing game: what movie will knock TDK out of the #1 spot? Admittedly, the competition isn't terribly strong over the next month., though with every passing week the chances of that happening get better. Here's the upcoming major releases:
July 25: Stepbrothers, X-Files 2
August 1: Mummy 3, Swing Vote
August 8: Pineapple Express, Sisterhood of Travelling Pants 2
August 15: Star Wars: Clone Wars, Tropic Thunder, Mirrors
And peeking at the next few weeks after that, it gets even lamer. I don't see any surefire hits until High School Musical 3 and Saw 5 in late October. So I'd say Mummy has as good a shot as anything else at being the first one to slip past TDK.
...godDAMN that's a lot of sequels.
Sisterhood of Travelling Pants 2. I'm calling it.