The posters / boards near the Mantles of Knowledge are woefully outdated. They most talk about solving the mysteries of Castle Avgardii which has been 'solved' for some time now.
I suggest they be updated to have these on them to maybe inspire PC's to seek them out in-game.
http://www.efupw.com/forums/index.php?topic=687613.msg689233#msg689233 (http://www.efupw.com/forums/index.php?topic=687613.msg689233#msg689233)
Cool suggestion, I agree. I had never actually seen the post you linked before so it was an interesting read and putting it somewhere IG (if it isn't already somewhere that I don't know about) would be even better for visibility.