Awesome. Absolutely awesome. It's great to see a MP game actually make it this far. I'm impressed.
A few of us have developed a similar concept over on the CK forums. Basically, we're trying to mimick a country's historical development by focusing on one kingdom and having each player control that kingdom for the life of a single ruler. When that ruler dies, the player forwards the save on to the next player and they continue the dynasty. Not MP in the traditional sense, but it does involve multiple players. We're intending to take it through HOI2 and I was getting a little disheartened by such a daunting prospect until I saw this thread.
Oh, and if anyone wants to take a stab at ruling the Duchy of Lappland for a few hours, details can be found in my sig