According to unnamed sources speaking to CNET, Microsoft is preparing to unveil its Windows 8 upgrade program for prospective Windows 7 PC owners. As we've seen in the past, the program would be intended to incentivize customers to purchase computers running current software rather than waiting for the release of the newest operating system. The sources claim that those who purchase a desktop or notebook running Windows 7 Home Basic or higher will be able to upgrade to Windows 8 Pro at a discounted rate. Though pricing remains unknown, the program will allegedly launch on June 2nd to coincide with the debut of the Windows 8 release candidate, and will last until January of next year.