Despite the fact that Windows 8 is expected to launch in October, Microsoft still has high hopes for its Windows 7 operating system. The software giant predicts that 350 million Windows 7 devices will ship by the end of 2012, Bloomberg reported. “It makes Windows the most popular single system,” Microsoft CEO Steve Ballmer said at a forum in Seoul, South Korea, although he didn’t provide any figures for comparison. Windows 7 was released in October 2009 and within two years, the operating system surpassed Windows XP to become the world’s most popular OS.