During an interview between GameInformer and Jeff Kaplan exploring the past and future of World of Warcraft, the developer revealed there will be a cutscene in patch 3.3, and they will further experiment with this in the Cataclysm expansion.
Kaplan: Cutscenes will always be something that we use sparingly, yes. We never want to interrupt gameplay too frequently or for too long of a period of time. The Wrathgate cutscene was a big experiment for us. It was our first foray into in-game cutscenes in World of Warcraft. I don