Please feel free to chill - today's announcement of direct messaging for everyone on Twitter is not just a Wild West situation. You will not be flooded with DMs this afternoon. While you CAN turn on DMs from anyone, this is not an open-door policy sort of deal. You DO NOT HAVE TO TURN THIS FEATURE ON. Twitter is just allowing DMs to appear in your inbox - IF YOU WANT THEM TO - from anyone on Twitter. Again - if this isn't clear enough - you DO NOT need to turn this feature on if you do not want to, and it isn't on by default.