There is actually a second part to this, entitled "I am so proud of you," which is equally enjoyable but not on Youtube. I highly recommend grabbing a copy of the DVD from Hertzfeldt's website (or pirating it if you're in a hurry).
I didn't say it was a departure. I definitely agree he had something to say with his previous work and I love it. But this says a lot more and just has an overall more serious tone than his earlier stuff.
YES! and you owe it to yourself to watch this and "I am so proud of you" seeing as how part three (the last part) is supposed to be coming out later this year. SO hooray. Also wisdom teeth is pretty damn funny.