Well, from the thread direction I guess I shoulda kept the Erlking speculation out of my OP!
I am building a story around what I put in here to start with, in essence a quest to find Oberon and bring him back in an effort to stop another war between Summer and Winter. In our game we have a particular gem for them to fight over, that being an independent faerie state named Emerald City (opposite of Seattle, WA in the Nevernever) ruled by dwarves (though they call themselves dvergar:
http://en.wikipedia.org/wiki/Norse_dwarves).
The same shadow groups that have been moving in the books are moving in our game. In this case they are slowly pushing for both courts to choose EC as their battleground for their next conflict, no matter how costly it is. At present neither side has moved to attack the city in force, but that's due to the delicate balance. In addition with the current state of the winter knight being inactive (yes, we've diverged from canon, right about at the start of TC), neither side is wont to disrupt the precarious balance.
However we come to it, I am loosely planning on the players' having a desperate bid to track down where Oberon went and then trying to convince this rather powerful being that they certainly couldn't fight to hie his hiney back to where it belongs in the natural order or things and restore a kinder balance between the two courts, perhaps giving room for the courts of Oberon's rule (as I have envisioned them) to flourish once more and earning some serious favor. After all they're going to need it. The Armageddon I have planned for this little shindig ought to need Faerie as their backup, since it took Marduk to kill it last time ;-)