Worth a repost for those who have not seen it.
http://www-10.lotus.com/ldd/dominowiki.nsf/dx/Understanding_the_IBM_Lotus_Notes_8.5.x_client_directory_structure
Thanks to Stuart for sending through this info.This article explains the changes that were introduced in the IBM® Lotus® Notes® 8.5 File System installation and describes them with respect to the installation, setup/launch/run, and uninstall phases in the client's life cycle. Also included are answers to some FAQs on the client file system.