Shopify for Japanese ecommerce

Shopify supports many languages and currencies including Japanese and Chinese. “The administrative interface of a shop is in English, but the storefront, checkout, email communications, etc, of a shop can be in any language.” (quote source)
Translating checkout interface language – such as “Billing address” and “Your order was placed successfully” – is a breeze. You can either simply select a set of translation if available, or translate a set yourself by filling out a form. There are currently 180+ phrases to translate but you can save and edit anytime.
Can you make a multi-lingual Shopify site with an integrated back-end of the store in the way Joomla! and Joom! does? No, Shopify does not do that. You can only use one language or currency per shop. So if you want English, Japanese and Chinese sites for your online shop, for example, you need 3 separate Shopify sites. You can connect these sites to each other for the site visitors to switch between them, but the back-end of the stores are managed separately.
This “limitation” may not be a bad thing, however. I have translated a Joomla! / Joom!Fish site and I think there are pros and cons in having a multi-lingual site this way. The main advantage of having separate sites for each language is the flexibility. You can customize everything on the site to the market, to the people you are talking to, from images in the top page flash to what products to feature to payment methods. Sacrificing this flexibility and autonomy of each site may not be a good idea unless the markets – buyers, competitions, online shopping method preferences, etc. – represented by the languages are similar to each other.
Here is an example of multi-lingual Shopify site that is actually two separate sites. The domains are http://www.bentoandco.com for the French site, and http://en.bentoanco.com for the English site. For shoppers, this is just fine. For the shop owner, he/she can show different products on the top pages if different products appeal to each market.
What about accepting JCB card? You can accept JCB card as long as the payment processing service you select for your Shopify site does. Shopify currently lists over 40 payment processing services (as of June 2011) including PayPal, Ahtorize.net and First Data (LinkPoint) as the ones that can be integrated to a Shopify site.