One of the biggest problems with Chinese e-commerce for the West has been the scarcity of a trusted online payment system. The Chinese do not have a great amount of time for credit cards, prefering cash. This is obviously a problem for any ecommerce that does not involve some face to face contact.
Alipay should be an interesting experiment. Although focussed on China at the moment, Alibaba made its money through linking up Chinese manufacturers to the West. There’s no reason to think that they won’t go the other way.