If we were to get a confirmed alien life signal from somewhere, I can assure you I would brown my undies. That would be the scariest/most exciting news of my life.
I do wonder how our scientific community would react to the news that a single celled organism was found. It's not the end all finding of "intelligent" life, but it proves life could exist elsewhere. Your normal Joe and Jane Six-Pack wouldn't give a shit about it.
As for humans going bonkers when reacting to the news that we found alien life, I believe it would happpen, but more so if they were to actually show up on Earth. The aliens land and then we meet them with torches and pitchforks. The human propensity for technological singularity and violence is quite well known.