The official documentation has moved to http://docs.couchdb.org — The transition is not 100% complete, but http://docs.couchdb.org should be seen as having the latest info. In some cases, the wiki still has some more or older info on certain topics inside CouchDB.
Entity Relationships: How to model relations between your objects in CouchDB
EnableErlangViews - How to enable the native Erlang view server (since CouchDB 0.10.0)
Additional_Instances - How to run additional CouchDB instances off the same binaries
Reverse Proxies, Virtual Hosting, Rewrites
Apache_As_a_Reverse_Proxy: How to put CouchDB behind proxy (for access control and/or high availability)
Language Specific Guides
Development and Contributions