It was briefly mentioned in the article, but this is exactly how couchdb shuts down:

On-disk, CouchDB never overwrites committed data or associated structures, ensuring the database file is always in a consistent state. This is a “crash-only” design where the CouchDB server does not go through a shut down process, it’s simply terminated.

http://couchdb.apache.org/docs/overview.html

(Please, no mongodb vs. couchdb wars here)