What Does Popularity Mean in a Nicheified World?

Does popularity mean anything in an increasingly fragmented world? Is this really the death of the mainstream, or is there a new mainstream evolving out of a more democratized, fan-controlled and inclusive definition? Popularity has become a new working framework for content that delivers the unexpected, connects people together and brings nuanced and individual experiences to a bigger stage. This new definition of popular makes sense of the paradox that despite endless channels and platforms, we still find people looking for big moments to come together over a shared love of characters, challenges, mysteries and love stories. How can marketers learn what will drive reach, engagement, re-watch, affinity and ultimately brand love via the matrix of the intersection of popularity and fandom?