"Orders are anonymous and are processed in the order they were placed (first come - first served)," the post from Community Lead Unuldur states. "Crafting an order will provide a player with the same amount of skillup and prowess as if crafting the same item for themselves."
This weekend also marks a special occasion to celebrate the upcoming prowess points respec with a Double Dye Drop Rate event and 2000 free prowess points for anyone with an active account as of May 31. Check out the official threads linked below for more info.
[Thanks to Dengar for the tip!]