Glyphs of the Keepers are Thief Guild reputation points. They show your level of contribution to the website content. Earn more and show others how wise fan mission keeper you are.
Here at Thief Guild we build a society of acolytes of the world greatest thief. Moreover we are also spectating adventures of many other interesting characters. Regardless we take care of the books or we take live action, the Keepers themself pay us their compensation. Who knows what powers will mysterious glyphs give us in the future. Only time will tell.