Lets see....
I think i would be a kind of almost mimic, not to try to put myself in the spotlight...
N E Way..
in real life what i do is i am nothing but the people arround me an a thin iron spike in the middle. I become those arround me, and if i'mm arround someone for a long enough period of time it takes a while for their trates to wear off. So i think if i was a vampire of this ilk i would probabaly have a mirrioring ability where if i was in proximity to another vampire, i would be able to use their abilities. Kinda like in Heroes, the guy that's going to explode NYC.
As a posible mutation of this ability, i'd be able to absorb other's aspects such as energy, health, streangth, endurance... what have you. In fact, in time (and by time i mean 50 years or so, i could probably take on other's appearances as well).