With Asia’s online audience and ad revenues still seeing healthy growth, The Nielsen Company has acquired South Korean audience measurement firm KoreanClick. The acquisition will give Nielsen access to over 30 markets worldwide and South Korea’s roughly 40 million web users. The firm launched about nine years ago. In addition to counting traffic, the company also offerings “attitude data” and has applications related to instant messaging, gaming and multimedia. Terms of the deal weren’t disclosed. The purchase comes a few months after WPP Group’s drawn out takeover of Nielsen rival TNS Media Intelligence. As part of its ongoing efforts to maintain its dominance, earlier this summer, Nielsen extended the JV with content security company Digimarc (NSDQ: DMRC) to cover the measurement of TV viewing and how users make purchases over their mobile phones. In general, the measurement business has seen a lot of other activity lately, such as QuantCast’s $50 million third round funding two months ago.