Fun fact: Martinet was also the voice of Paarthurnax, one of the dragons in Skyrim.
Also, I can't believe that Nintendo's own tweet about this announcement got one of the facts wrong. They wrote:
Charles Martinet has been the original voice of Mario in Nintendo games for a long time, as far back as Super Mario 64.
He was actually the voice of Mario before Mario 64. His first official Mario role was in Mario Teaches Typing, which came out two years before Mario 64.