Your words have extra weight today, so be mindful of what you say. You can't just toss off whatever comes to your mind: think through what you are about to say! And if you offer criticism today, give concrete examples. Help people understand what you mean, or else they could just get defensive and reject what you are saying out of hand. And don't forget to make it clear to them that you know they are capable of amazing things. They need to hear it.