Lots of interesting stuff here. We meet one of the "Rogue Jedi Knights" hinted at months ago; and though we don't really learn much about Nom Anor himself, we learn a great deal about Rhommamool and Anor's followers. We also see yet another example of Jaina's affinity for flying.
Most intriguing of all, we learn of a strange disease plaguing Mara. Not much detail is given on the nature of the disease, but it is almost definitely made out to be fatal. It even says that Mara needs the force to hold it at bay. SPOILERS? This adds Mara to the list of possible deaths.