I am developing a content site for Japan and wanted any leads on the best provider for payment processing - I would like to accept credit cards (that are typical in Japan) as well as cell phone payment if possible. Business is a US company Thanks
GMO Payment Gateway is probably the largest provider for payment processing in Japan. It's run by the GMO group, a public company here. This is their website http://www.gmo-pg.com/ but the page is entirely in Japanese. Obviously there are many other options too but depends on what you're selling. Feel free to PM me.
I also know that payzeno.com is a good processor of payments through cell phones, worth looking into.