People isn't even what you have to be good at, it's not enough to be a very social person, because people act really differently online than they do IRL.
Being Very Online isn't even what you need to be good at, because that only gives you an end-user's perspective, which is useful sometimes but way less often than you think.
Really the only thing that can make you good at admin'ing an online community is doing it for a long time and talking to other admins.