Download the patch from the usual place.
Everything is now translated (except for the credits). This includes the Friends/Monsters/Quests images in the Memory section.
As far as we can tell the subtitles do work as long as you have a proper codec pack like CCCP.
There will be a "final patch" later containing fixes for any errors people report with this patch.
Also, once you're done reading it, consider submitting something to the Key 15th Anniversary Letter Project.