YouTube comments are the butt of many jokes; read a few and you'll know why. Randall Munroe created an XKCD comic in which a character invents a virus that reads YouTube comments back to the commenters before they post. Read the entire strip here. Now YouTube has installed an "audio preview" button that reads a comment aloud before its posted!
Whether “audio preview” will make any difference to someone whose entire comment reads “rrrrrrrrrrrrrrrrrrrr” (actual comment from a featured video) is to be seen. I’m guessing most commenters will skip right past it in an effort to get their “first!” comments in there.
The placement of the button is interesting. It’s exactly where the post message button used to be, meaning quick commenters will discover it only when they accidentally click the new button. Hopefully they’ll do this with their speakers up at work.