It's old news and every Bat fan has probably visited that site by now. However if you haven't you should really check out. http://www.whysoserious.com/
Not too much to it, got a new shot of the joker some werid clues and another website called rorys death kiss. The site allows fans to submit pictures of themseleves as the joker.
Some of the stuff out there is pretty cool. Fun times.