Anne Stickney over at WoW Insider has posted this theory.
In short: Azeroth is the embryonic "final titan" (see patch 5.2) that is infected with the Old Disease, life (dragons, mortals etc.) was created as an "immune system" to cure Azeroth without killing it. Algalon represents abortion as the ultima ratio.
I think it is a fun theory. Unusual, if nothing else.