The interesting ideas with Mongrel2 were 1. Being able to automatically adjust your configuration/db on the fly 2. Using ZeroMQ for everything so that you can

The interesting ideas with Mongrel2 were 1. Being able to automatically adjust your configuration/db on the fly 2. Using ZeroMQ for everything so that you can tell your backends about your frontend and not vice-versa. Turns out neither one of those is really worth changing away from a static configuration like nginx or apache.