Includes 2 billion dollar cash, 12 billion dollar stock. Assume the additional stock is sold at $50, QIHU needs to issue 24 million shares to cover the transaction. With about 120 million shares outstanding before the deal, the current shares are going to be diluted roughly by 17% (120/(120+24) ~= 0.83).
Of course this deal will give QIHU roughly 30-35% search market. However, such sizable acquisition is highly likely causing short term pressure in the stock price.