This is truly awful for the US market. May make sense in Asia, but I can't think of a single relative who would buy something from here. Buy.com was at least a somewhat trusted name; this is just asinine.
That's not a name change, per se - Rakuten (楽天) is Japan's largest e-commerce site, and recently has been expanding overseas. They also own Play.com, Linkshare, and Kobo - it appears they've decided to get all of their websites under the Rakuten branding.