Expedia Inc. EXPE, -0.01% said Thursday it has agreed to buy Orbitz Worldwide Inc. OWW, +21.83% for $12 a share in cash, or an enterprise value of about $1.6 billion. Orbitz shares surged 23% on the news, sending rival online travel site TripAdvisor Inc. shares TRIP, -0.30% up 15%. Expedia said the price offers a premium of about 29% over Orbitz' average share price for the last five trading days. Expedia will hold a conference call at 8.30 a.m. Eastern Time to discuss the deal. Shares rose 3.5% in premarket trade. http://www.marketwatch.com/story/expedia-to-buy-orbitz-world...