This patch will update The Lord of the Rings Online: Shadows of Angmar clients from Book 13 to Book 14. It will not work for the Roheryn public preview server.
The downloadable patch means you can download it and patch your client before the update goes live on the servers, saving you time when they come back up. It also means you can download the patch on a computer that you don't have LOTRO installed on (i.e. your work computer), transfer the patch to a disk or device, and then run it on the computer with a LOTRO client to update it. After you've updated your client, when the servers go live with Book 14 your client will apply the patch and update itself.
IMPORTANT NOTE: This file will ONLY patch the North America/AU/NZ version of the LOTRO client. If you try to apply it to the EU version, you'll get an error message.
Full release notes for Book 14 can be found at: http://lorebook.lotro.com/wiki/Release_Notes_Book_14_Official