This is a phrase stolen from strategy consultant Geoffrey Moore. He wrote about the chasm as part of the technology adoption life cycle, defined by innovators, early adopters, late adopters, and laggards. Similarly, we are seeing a chasm being crossed in the coworking industry. As coworking crosses the chasm and late adopters get on board, it is finally becoming mainstream. See the white paper- The Coworking Industry: Then, Now, and the Future for more.