It's actually a 17% off deal if you're an executive member (really it's the only way to go).
Ever since last years big eBay sale of $50 iTunes cards for $35 I've been holding out for a similar 30% off deal. This Costco deal is only 15% off so not enough for me (yet others will like and appreciate it).
Wow, and just like I said earlier, Paypal (its digital-gift website) had a 50% off iTunes gift cards until finally selling out 3.5 hours later.
I bought $100 worth before they stopped me from buying any more.