In trying to catch up to speed on lore before Skyrim, I was wondering if we knew what the heck befell our friends Sheogorath and the Champion of Cyrodil? I've played Shivering Isles, but it just raised more questions. Is Sheogorath forever replaced by Jiggylag now (tragic, if true), or are they separated somehow? Does the Champion of Cyrodil just retire to run Sheo's old realm and that's that for him?

Maybe I missed some text in-game that divulges, but I was wondering if there's been any new insight onto these characters with the marching progression towards Skyrim.

The CoC became Sheogorath. It's not quite clear yet whether Jyggy managed to break free completely.

http://www.imperial-library.info/content/arden-sul

Well that would explain quite a bit, and would seem to lock the CoC's fate as Sheo. But from the description of a mortal taking on the mantle of Sheo, it doesn't quite make sense to me why they have to lose their physical form when Jiggy arrives. I don't see why the two antithesis could duke it out physically themselves. I don't understand what would make the mortal have to turn into either/or. Seems like cosmic voodoo.