By Daniel Kline Facebook has bet its future on technology that people may not actually want. Predicting the next big thing has been notoriously hard. Remember when 3D printers were the future? How about the upcoming dominance of 3D television or people fleeing New York City never to return? How about when Napster seemed like the future of the music industry or MySpace seemed like an unstoppable social media powerhouse. A lot of next-big-things become either not a thing or a much smaller thing than people expected. 3D printing, for example, has not become a major part of life for the average Am…