Noone seems to have explicitly noted this yet, and it's driving me nuts:
That's not what a philosophical zombie is. Like, it's amost the exact opposite, actually, the whole point of a P-zombie is that it acts exactly like a person in every way, but has no internal experiences. The argument made using them explicitly rests on the fact that it is in principle impossible to tell that another person isn't a P-zombie - literally everyone else in the world might be a P-zombie, for all you know, because you can't tell what other people's internal experiences are like. Behavioural markers like lack of empathy and concern with one's own advancement cannot possibly distinguish a P-zombie, both because that would be an external difference (which P-zombies don't have) and because something can be inhuman and have experiences. Nor could one make a P-zombie, actually, since there's no way to really know that something isn't conscious either.
(For the record, the major argment using P-zombies is, simplified: 'P-zombies are not in principle a logical impossibility, therefore it is logically possible to have a being physically identical to a human without internal experience, therefore our experiences are not identical to anything physical, therefore physicalism is false.')