For those who don't care about remaining anonymous and don't care about centralizing their personal Bitcoin (depositing Bitcoin onto an ATM card would be a form of voluntary centralization), it might be a very convenient way to spend their bit coin. At this point, I would be extremely leery of any ATM cards. The major payment processors (VISA and MasterCard) are not open to the idea of Bitcoin and could force the card issuer to stop excepting Bitcoin deposits with little to no notice.