I don't know what to say! I adore Tricia and I always lamented she didn't have more screen time with Jamie on Battlestar Galactica. Plus, I called this one! :D After reading the sides, I totally saw her in the role of Morgana.
On the flip side of this news, as happy as I am, this is three actors now cast from Battlestar Galactica. I would say Ron probably should stop there. ;)