The truth is, most people will stay on Reddit, at least in the short and medium terms. But with each migration wave, there is a group that will stick around and make things just a little bit more active and interesting, and make it that much more appealing for the next wave.

I predict the next wave is when Reddit inevitably announces the shutdown of old.reddit. Now there will be a more viable alternative for that migration wave, and so on, until we hit critical mass.

That's the hope, anyway.