Not counting the class items, there are 15 pieces of exotic armor for warlocks, and 16 for hunters and titans. There were nine pieces of armor in the database before TTK launched that were not released with the DLC. In a later patch, the Tarentella and the Twilight Garrison were added. No new warlock armor was made available. With this latest patch, the remaining seven items were removed from the armory listings. What gives, Bungie?
Keep in mind, warlocks have 3 class perks that are only attainable to titans through exotic armor. So really, warlocks have 18 exotics