Skyrim - Dawnguard Video Gmeplay Demo

G4TV has around five minutes of Dawnguard footage with input from Todd Howard. You'll get to see all the major features, such as Vampire Lord transformations, crossbows and so on.
More information.

This is looking great. I might just reinstall Skyrim and give it another chance with this. Can't wait to see how the crossbow action is (besides other cools things) and please dear Odin let it have spears!