A few things come to mind:
- Number of followers
- Follower/following ratio (FFR)
- Their tendency to use @mentions (TUM), making it more likely one of their followers may find/follow you via network effects
- The vigor of their genetic health and suitability for the future production of progeny (VGHSFPP)
- Their consistency of output – if they have great answers, but produce them rarely, you're better off following one of their followers
Besides the quality of their content, what makes a Quora user more desirable to follow?
deano.com 