Odd, today I opened my mail and found a $30 GC too - even though I'd entered their contest on the first day VERY early in the morning, after reading all the comments from those who'd entered later that they were wondering why they had won the same GC I thought it was a software error.
Glad to see it wasn't! Now I'm thinking of cashing it in using Plastic Jungle but I'm not sure if I'll do that - OD has some nice sales.