No, CouchOne the company and Membase the company merged and became Couchbase the company, but CouchDB the product and Membase the product remained separate, except that Membase the product was now called "Couchbase" after the company. Their naming is a bit confusing.

Couchbase and CouchDB have similar name but both databases are quite different. A slightly dated comparison of CouchDB vs Couchbase is at https://www.couchbase.com/couchbase-vs-couchdb. We are in the process of getting that updated.