I think it's great to see someone make a run at a more decoupled ruby web app approach. I hope it succeeds. In my experience working on Obvious ( http://obvious.retromocha.com ) it is hard to get Ruby developers behind decoupled architectures because the large majority aren't Ruby devs, they are Rails devs and Rails happens to be in Ruby. Also, the larger group of developers doesn't like the idea of an app being a gi…
One problem I have with "decoupled" architectures is that the only way you can sensibly interop with everything from RDBMS to flat JSON files is if you treat the RDBMS as a flat file. For instance, the sample Twitter clone treats every available DB as a plain key-value store.