Seriously love this product. What the Realm guys are missing is the fact that Couchbase Lite is really a replication protocol overlayed SQLite. Couchbase Lite did not always use SQLite and is in the process of switching to ForestDB as the underlying persistent store. As far as API's go, I have not seen a more intuitive design than CBL's. It almost makes too much sense. Once you get Sync Gateway setup, you have a mini iCloud. Watch the CloudKit presentations and you'll see that CBLite solves what Apple is leaving up to developers as far as Sync goes.
I think that's because Cloudant's solution is the same replication protocol (CouchDB) talking to it's hosted databases. Thank's for pointing this out, I didn't know about.