Sina (NASDAQ:SINA) unveils plans to offer an Internet TV service that will be integrated with its Weibo microblogging platform. Sina has been investing heavily in Weibo, which now has over 300M registered accounts, as it tries to keep Tencent (OTCPK:TCEHY) at bay. Sina Weibo's traffic easily outpaces that of Tencent Weibo, but the massive reach of the latter's QQ messaging platform still makes it a potential threat. (previous)