Steven Sinofsky, Michael Angiulo and Panos Panay present Microsoft's Surface tablet computer in Los Angeles

Steven Sinofsky, president of Windows and Windows Live Engineering Group at Microsoft Corp., left, Michael Angiulo, corporate vice president of Windows Planning, Hardware and PC Ecosystem, center, and Panos Panay, general manager of Surface (L-R), presents the company's Surface tablet computer at a news conference at Milk Studios in Los Angeles, California, U.S., on Monday, June 18, 2012. Microsoft unveiled its own Windows-powered tablet computer called Surface, altering its strategy of focusing on software and relying on partners to make the machines in a renewed attempt to take on Apple Inc.'s iPad. UPI/Jim Ruymen