First off, the confirmation email you guys sent me clearly states: "We have made a direct deposit into your MTGox account and there is no need to use the coupon system on this order" So why I'm now being directed to enter in a code is beyond me..
Secondly, MtGox support told me to try entering that code LONG before I had even created my account here, let alone posted that info. So if someone did steal my code or whatever, it surely wasn't from my posting that reply because when I tried to use it before, long before I had posted any of that information here in these forums, it gave me the same error message, and I have not posted it anywhere else. Just in emails to MtGox support.
Same thing happened with me!
I got a email saying "We have made a direct deposit into your MTGox account and there is no need to use the coupon system on this order" after I paid my order.
My funds didn't show after a couple days so I contacted bitinstant support and got a reply from Mandrik. He tried to say I didn't provide a valid account # so the system gave me a coupon code. Thats not true though I did provide the correct account #. As soon as Mandrik gave me my Mtgox coupon I tried redeeming it and it says "This code cannot be redeemed (non existing or already used)"
I've been trying for a week now to even get somebody to answer me why I was provided with a Mtgox coupon that doesn't work. Still waiting for a reply from bitinstant!