As a teacher, I love to watch how others teach. I do this because I am always looking to improve what I do for a living. By using You Tube and TeacherTube a teacher can have access to various relevant videos pertaining to a topic they are teaching or wanting to gain knowledge from. Or it can provide another teaching tool for the students to learn from. For example, if there was a topic a teacher felt they were a little less knowledgeable in explaining, they could play the video for the students and have someone more knowledgeable explain the topic. Or a teacher could simply use it to change up the atmosphere in their classroom for a moment. I know I personally use it for coaching purposes all the time.
Being able to upload videos for assignments would give students and teachers 24/7 access to turning an assignment in. For instance, a teacher could have a classroom page setup on Facebook and could have an assignment where students have the option of uploading their presentation through youtube and posting it on the Facebook page.