What is the Gunsmith reputation for?

Before The Taken King, the following factions allowed you to gain reputation to purchase new weapons and equipment:

Vanguard, Crucible, Dead Orbit, Future War Cult, New Monarchy, Crota's Bane, Queen's Wrath, House of Judgement, and Iron Banner

After The Taken King was released, the lonesome vendor that nobody ever visits, the Gunsmith, now has reputation. However he does not possess any items that are purchasable through increasing your rank.

Does anybody know what the reputation for the Gunsmith will be used for?

My only speculation is that it would be similar to the Cryptarch where you obtain additional items for each rank after rank 3.

The gunsmith has his only weekly event called Armsday which allows players to order from a selection of 6 legendary weapons of random type and manufacturer. The ordered weapon is delivered to you via the Gunsmith the following Wednesday (Armsday), the weapons perks are randomized and are not the same for every player. At this time his weekly field-test weapons and weapons available for ordering will also change.

Players can start ordering weapons when their reputation with the Gunsmith is at least rank 1. You can place 1 order at rank 1 with the gunsmith and as you raise your rank you are able to place additional orders per week.

He also gives quests at ranks 2 and 3 that gives class-specific rewards. Rank 2 rewards a legendary special weapon, and rank 3 rewards an exotic primary.

As Justin notes, there are three ranks, and at each one there are rewards.

• 1) Place one order for a weapon each week. There is a set of these you will see if you are rank 1 or above for sale just beneath the testing set he sells.
• 2) Place two orders for a weapon. The item purchased is 2500 glimmer and remains in your inventory until redeemed each week. In addition, receive a bounty which awards a legendary class weapon.
• 3) Place three orders for a weapon each week. In addition, receive a bounty which awards an exotic class weapon.

When purchasing a item to redeem, the item must be held until wednesday at which point it may be obtained by trading the placeholder item in. The weapon redeemed will have the same roll on it that week for everyone, but each week the roll will differ.

Obtaining reputation with the gunsmith goes very quickly. It is fairly straightforward. The gunsmith sells weapons which are common (200 attack rating) and in each weapons description there is a checkbox which details a way of "charging" the weapon. Completely this to 100% will yield reputation with the gunsmith, it does not need to be turned in, and can be dismantled upon completion. It is 250 reputation awarded per completed weapon test. The weapons available for testing reset once per week on wednesday.