Many sites have videos and/or articles about Destiny: The Taken King, and I've been doing my best to keep up! Here are a few of my favorites so far:
IGN - Multiplayer footage of Rift, Destiny's new Objective based multiplayer mode (look at all those new weapons!), along with DeeJ discussing the game with Destin from IGN. Also revealed Playstation exclusives will be available for Xbox, and the fact that you can skip cutscenes when Taken King drops. (Thanks iconicbanana)
Kotaku - Information about the first campaign mission that press got to play behind closed doors. (Thanks INSANEdrive)
Reddit - SonOfSeath on Reddit put together graphics of what the new upgrade trees for each subclass looks like (right now).
There's a lot of other interviews out there, pretty much go check any video game news site and you'll find someone talking to a Bungie employee!