Considering that, 1. waiting [10 minutes for confirmation][1] is too long in the retail world; 2. "zero confirmations" will become more risky once bitcoin popularity is high enough and people come up with services (automatic scripts) that try to do massive double spending, why should retailers consider bitcoin over other cryptocurrencies that have shorter confirmation time, and therefore less potential risk? [1]: http://bitcoin.stackexchange.com/questions/7323/how-long-does-it-take-on-average-to-receive-one-confirmation-is-it-still-revers