Batman-News were clued into the existence of a QR Code on the final theatrical poster (the physical copies, not the online version) which unlocks an online exclusive poster. The image highlights Catwoman, bringing the high-heeled wrath down on a batarang. See right, click to enlarge.
Most of the imagery is reminiscent of one of the original teaser posters and the recent "Rain" themed character posters. There is an emphasis on destruction, with the rainfall resembling debris.
Also worth noting is the way the Batman symbol is visualised through a lipstick imprint. It's a more sultry spin on the pre-existing marketing, Catwoman leaving her mark the grim and gritty world of Batman. Ever the rebellious type, as seen in her dedicated TV spot.
It works for me, it's a striking image while also slyly character-driven.