The top friends visible on a profile on a FB user, are these the friends the person is interacting most with?

[a_ferocious_coug]

I think they’re a mix of who you interact with the most and the friends you’ve added most recently. I’m not sure if everyone sees the same friends there though.

[the_timps]

No, they aren’t.
Facebook isn’t surfacing someone else’s user data to you. That’s a huge privacy issue.
The top friends appearing there are the ones Facebook thinks YOU have the closest connection to.