On Linux, installing CouchDB involves installing so many dependencies, some of them are incompatible with ubuntu/debian installations. Fortunately, a binary distribution with all the binaries is provided by CouchOne.
The problem with that distribution is that it is interactive and it won’t be possible to automate the installation of that. To overcome this problem, the binaries after running the interactive installation are taken and bundled. The ol install script, downloads the bundle, unpacks it and runs a script to updates the path in some scripts and config files.
The created bundle couchdb-1.0.1-linux-binaries.tgz is uploaded to http://www.archive.org/details/ol_vendor.
On Max OS X, installing couchdb is somewhat easier than installing on Linux. However to make the installations on both mac and linux similar, binaries are taken from CouchDBX app.
Unlike Linux, where bin and etc are available in the top-level, mac binaries have them at 2 level deep. To make both distributions identical, a bin/couchdb script is added and etc is symlinked from couchdb_1.0.1/etc. Also the mac couchdb script expects the base directory should be the working directory. The above bin/couchdb script, takes of this too.