-a new Scenario Pack - The Angered Fae. Someone in the village has unwittingly upset the fae, who are now causing havoc with your friends and neighbors. The heroes will have to traverse the realm of the faeries in order to settle the matter.
-a much extended Bestiary (almost 50 new monsters). We really tried to focus in on monsters that would "feel" particularly Beyond the Wall. We have also included lots of story hooks in the Bestiary to help GMs come up with quick adventure ideas that, again, "feel" like BtW.
-some new spells (13 to be precise).
-some extra rules material and advice on skills, perception and searching, and group activities and the helping rules.
-our version of a simple reaction table and using your Charisma to impress NPCs.
-some more on hirelings, including tables with prices and some suggestions about hirelings becoming Allies.
-a small, but super cool new rule regarding true names; there is a reason now to share your true name with your closest friends.
Some of those changes might not please all OSR fans (Charisma, things like perception), but on the balance it sounds good to me.