definitely a combination of creators with: most likes, most zapped, notes/replies activity, tag/mentions -- all of this within a reasonable timeframe. 

it's a matter of finding the sweet spot before you can just zap your way in, so a mix of all factors would favor a legit creator.  

 Problem is most zapped/likes/activity only works with an existing web of trust or else it can be gamed 

 wash zapping renders it a useless metric