the Korean social giant that could, finally couldnt. At least not in U.S. It is shutting down its U.S. service, after three years of trying, according to a notice on its site. It will shut down in entirety on Nov 23. The service, owned by SK Telecom (NYSE: SKM), the biggest telecom firm there, entered U.S. in 2006, and said it would $10 million into launch. The parent company also said a year later it would invest about $110 million in online businesses in U.S., and that hasnt happened either....

