"You cannot replicate between a CouchDB database and Couchbase Server."
It's written here
http://docs.couchbase.org/couchbase-manual-2.0/couchbase-int...
Also,
"Almost all of the HTTP REST API that makes up the interface for communicating with CouchDB does not exist within Couchbase Server. The basic document operations for creating, retrieving, updating and deleting information are entirely supported by the memcached protocol."
Querying views and map/reduce functions in Couchbase server will be similar to CouchDB except the output will be slightly different.