Earlier quoted context omitted.
> it's an unlikely success story that deserves admiration Well, it's a success story due to marketing, smart marketing, clever marketing, and more marketing, not due to lots of technical merits. And it was not the first document store to appear, just the most successful. For starters, CouchDB was previous to MongoDB.
Couch was a nightmare to use, mingo made all the friction to get it into products go away, especialy when teamed with dynamic languages.
We used replication on the native apps for offline mode, kept things simpler with online-only for our web app, and have had a very good time overall.
We are also using JSON schema for our CouchDB documents so we ensure we don't have all kinds of wild / wrong data showing up; if you had really hairy, unstructured data, I can see why a dynamic language might help with that bad situation, but for our use case, we were able to take advantage of the powerful replication built into CouchDB and get solid offline syncing for all of our native apps that also plays nicely with live updates in a web browser.