[winmysoul]

When you buy WoW you get a free month and then every month after that Blizzard bills your credit card. The game cards you mentioned are good for 60 days and cost $30 USD. You can pay monthly, every three months, or every six months. Unless you cancel the account Blizzard will continue to bill the credit card. If you're using game cards then your account will be unplayable the 61st day after you registered that game card until you register a new one. So the price breakdown is the cost of the retail game(twice if you're also buying the Burning Crusade expansion), a one-time cost, plus the subscription fee which include the periodical credit card charges or expenses toward the purchase of 60-day game cards.