Online video use continues to climb in China. A study issued Thursday by Chinese Internet tracker iResearch says the country's No. 1 Web TV provider based on daily user traffic is PPTV, with more than 34 million unique visitors in May. In second place, at more than 33 million, was Youku (YOKU). PPStream was third with 32.5 million, followed by Tencent with 25.6 million, Sohu (SOHU) with 20.1 million and Tudou (TUDO) with 18 million. IResearch says