This seems really fun. I'd love to be able to use this almost like a version of SQLlite, but a JSON interface.
I could see this in Android/iPhone, as well as Desktop apps.
CouchDB already has embeddable ports to Android and iOS, and it has the added benefit of a built in master-slave or multiple-master replication system, so you can have your app get and push up to date data from a server when a connection is available, but still be fully functional without it, for free!