The wrapper is called PHPillow, lays on top of the Couch and offers even more comfort laying anything into the database. :) It has complete API documentation, currently a test coverage of >95%, tutorials and practical examples included. Even I would call it alpha - as CouchDB is still alpha at the current state - you can expect it stay quite stable API wise, as I rely heavily on it in other projects and therefore won't break too much.

You can check out the latest version of this wrapper from its subversion site and get more information about CouchDB on its website and wiki.