Re: TDKR SPOILERS (read at your own risk) - Part 5
Article says it was a clever fanboy and that the crowd made their own signs. I'm not so sure, seems like exactly the kind of easter egg nolan would leave for us to pick up on subsequent viewings. at the very least i think he must have seen it in the audience and loved having it has something to throw in the movie.
ps i'm a huge robin fan, i'm the younger of two brothers and have kind of always felt like the sidekick in a way - i loved seeing any reference to the character in the nolanverse and appreciate the realism nolan brought to his spin on the boy wonder. fan-friggin'-tastic
this may also be one reason why i am so happy with the ending of the movie.