I've seen a lot of people claiming that the Blacksmith shader will be obtainable in the game, and that the preorder is simply early access to the shader. The few that do cite a source use the fact that since the Blacksmith shader is in Destiny DB, must mean that it is obtainable in the game. This is not true. The Blacksmith shader's presence in Destiny DB is not proof that it will be obtainable through normal gameplay. It simply means that it exists in the games code. There is no reason to believe that this preorder bonus (because that's all we know it is right now) will be obtainable in the game without having preordered COD. Here are two examples to help further my point: 1. Mew, Pokémon number 151, is in the code of every single main series Pokémon game. If you were to hack these games and analyze their code, Mew would be in there. But there has never been a single major Pokémon game in which Mew has been obtainable without going to a special event or downloading it as part of a special event. 2. The "Ghosts" category of Destiny DB lists various Ghost casings that are apparently in Destiny. One of these casings (skins, essentially) is called the Frontier shell. The Frontier shell is the Ghost skin that you get for buying the Limited or Ghost edition of Destiny. Obviously there will be no way to obtain this skin through normal gameplay, and there is no reason to believe that it will ever become obtainable post-launch (whether by paying or playing), as Bungie has said multiple times that they want "Limited editions to be truly limited". If you like the Blacksmith shader (or you're a completionist like me) then you should get the code now. You can cancel your COD preorder after Destiny releases to get your $5 back.
Another thing to point out is that on [url=http://destinydb.info/vendors/3917130357]this DB[/url], the shader is under Special Orders, along with the Limited Ghost and pre-order Sparrow.
I seen pics of the blacksmith shaders a while back. Unless they changed things, which is very possible, it will be available without pre-order. I'm going to risk it out of spite.