Surprisingly, viewer engagement does not consistently correlate with overall viewing numbers. VentureBeatlists five common traits among channels that have the most engagement, as identified by the SimulTV study:
1) Post new content at least twice a week.
2) Participate in the discussion; talk to fans and subscribers.
3) Link directly to your Facebook and Twitter accounts, plus consider your Google+ or Tumblr accounts.
4) Use playlists to group videos with similar themes and showcase best-ofs.
5) Design eye-capturing thumbnail images for your videos instead of relying on YouTube’s screen grabs.