It's an entirely new engine. very little of the existing game will be taken. the only thing that might be salvageable is the textures for armor etc. almost all of the animations have been reworked due to the new engine.

seeing as they have the capacity to e-mail all of us, it will likely be a link via e-mail where we will DL or we might recieve some sort of special code and DL via the SE store.

They have implied it will be a digital delivery. but we will of course have the option of purchasing a a hard copy. although a lot of us probably won't bother. (unless there's a cool CE)