*Spoilers*
From what I have at least seen this is what we are getting:
1.A new full auto pulse rifle
2. All new weapons seem to be able to injure the more powerful hive (making them useful in and out of the raid)
3. Some weapons can pierce the Knights' black shield
4. Some weapons will mark the target after dealing damage
5.Chest pieces give a boost to a buff within the raid,
6.Gauntlets increase reload speed of all special weapons
7.Helm's give another boost while the raid boost is active as melee cool downs for dealing grenade damage
8.Boots give increase special ammo an a boost in agility when carrying the sword of a sword bearer.