The purpose is to have a dialogue about what we are building - admittedly it makes more sense with a voice over explanation.
Yes, "now" is a niche filled by doingtonight. It also highlights trends in the market that doingtonight builds on (blogs > twitter, kodak gallery > instagram, etc).
Similarly, "then" portrays the problems we are trying to solve (or markets we are trying to make more efficient) all within the context of "life at night".
