So, I found some of the special rules for the Wolves. Let's just say it involved a magnifying glass and going slightly cross-eyed. I know some, if not all, of these have been leaked, but I thought I'd mention them anyway.
Canis: Can replace his attack characteristic with the number of enemy models in base to base contact with him. He also allows you to take Wolf Guard on thunderwolf cavalry.
Njal: Has a 2+ armour and a 4+ invulnerable save. Lord of the tempest: in addition to his other psychic powers, Njal can impede the advance of the enemy by hitting them with chain lightning.
Logan Grimnar: He and his squad get to choose from Fearless, Tank Hunters, Relentless, or Preferred Enemy. He makes Wolf Guard troops, making the all terminator army "viable."
Ragnar: He and the unit he joins have Furious Charge and add +d3 attacks instead of just +1. He still has a 4+ invulnerable.
Lukas: He is an upgrade to a Blood Claw unit, and he does not count against your HQ choices. All successful to hit rolls against him must be re-rolled.
Ulrik: He allows one model in the army to add +1 to its WS, same as before.
Rune Priests: Runic Weapons are force weapons that can also negate enemy psychic powers.
Drop Pods: They only have a capacity of 10 models, 5 terminators, or 1 dreadnought.
I don't really care about the drop pod nerf, though it does seem arbitrary. I've heard similar rumblings concerning the standard Land Raider, but I've already expressed my disdain for this model in a Wolves army.
Ragnar seems like he's going to be murder. Unless he costs a ridiculous number of points, he's going to be almost mandatory, especially if you run Blood Claws and that ability stacks with Berzerk Charge.
Later,
Monkey