On the wiki it seened like you could only possess certain humans (civilians, guards, Tall Boys) which is pretty lame. If you can posses one, why not all?
You can possess all living things.
So, what I want to know is can you possess a target, perform the assassination by jumping off a ledge, unpossess then blink into another target so you don't splatter all over the ground? That'd be sweet.
You can do that as well. Apparently, the gameplay shown to the media-sites had a scenario in which Corvo jumped from a balcony and possessed a guard stationed on the ground. This does make me wonder, though, what happens to Corvo's physical presence (i.e. his body) when he possess his victims?
http://kotaku.com/5905231/18-things-about-dishonored-you-should-know