I was watching some clips of the FuwaMoco JP stream from earlier today (yesterday? depending where you are) and there was debate in the comments about their native language, accents, etc. and someone mentioned their debut video of when they were GGN. If you want to hear them speaking "normally" before they adopted the cutesy/moe voices, it is pretty interesting.
WTF?! There voices were fake the whole time???? I CAN'T BELIEVE IT!!!!!!!