The old system of the vampire skill line was somewhat, backwards? The more you fed the weaker you got, vampire stage wise. Clearly that makes no sense since everyone knows that if a vampire feeds, they should get stronger.
Zenimax Online Studios have recognized this and are now pushing the Vampires in the Elder Scrolls Online into a more active role, where if you feed more, you gain power! Just like a vampire should be.
We know that we are getting some NEW skills to go with some potential old skills but no details at this point as to what that will entail. We do know that the vampire biting animations are also going to look MUCH more…feral? In ESO Vampires tend to channel blood from their enemy from range for a couple of seconds and then it is all over.
However Rich Lambert noted in the release stream that they are looking at a more Dark Brotherhood style execution where animations will appear to be physically interacting with the victim making it feel like you are actually attacking your target and feeding off them!