Apparently, there will be Chitin, Bonemold, Nordic and Stalhrim armour in the DLC, though it's not really confirmed yet. (But I think the trailer showed Bonemold and Nordic) The trailer also showed some kind of more magey armour, perhaps used by the first Dragonborn's minions.
I'm speculating that perhaps there might be weapons made of these materials as well. Also, spears are confirmed, BUT it is not confirmed that the player can use them yet because the trailer only showed Reiklings using them.
I'm wondering how the armour types will be classified though. If there aren't any new perks/skill trees, I'm thinking Chitin and Bonemold would be Advanced Armours, Nordic would be steel and perhaps Stalhrim would be under Glass. (For smithing) As for the spears, they might use the existing two-handed/one-handed skill trees or they might even get a skill tree of their own, but nothing has been confirmed or rumoured about their skill use. However, since they never showed the player being able to use spears (which I think would be a big feature in the DLC) I suspect that the player won't be able to use them.