No, I didn’t mean ALIENS I meant, they confirmed UFOs, and nobody could care less! And also, the Yeahhehehehhah!!!!!!! Is a reference to the next scene in the movie.
I think think the reason no one cared is unidentified flying objects are still unidentified. We all knew about them, even if the government was being tight lipped. So we don't know anything new (except perhaps the strictest of sceptics determined that there was nothing to see).
As for the movie reference, I'm not a movie person so I still don't get it. Sorry.