Will this affects price?
GMO is a Japanese trading platform for Forex, Equities, Stocks and now Bitcoin, it is insured for hacker attacks and regulated by Japanese Financial Services Agency
in japan bitcoin is already very big they use it like they use their jpy or yen, it's hard to think that it would make any difference there in japan, if it was another country where bitcoin is not very known perhaps yes, but nonetheless it's a good thing more exchange more possibility to have more people that buy bitcoin