Late last week, Microsoft Corp. announced the availability of the Windows 8 Release Preview, the next milestone of the highly anticipated Windows 8 operating system. Available for download now in 14 languages at http://preview.windows.com. Since the February release of Windows 8 Consumer Preview, which was downloaded more than a million times in the first 24 hours, Windows 8 has become the most tested Microsoft operating system of all time, and with today’s release, enters its final phase of development before it releases to manufacturing. 

Primary Changes from Consumer Preview to Release Preview:  Windows 8 Release Preview delivers new Windows 8 Bing Travel, News and Sports apps, as well as Gaming and Music Xbox apps that integrate with your Zune pass. The Release Preview also features notable improvements to the Mail, Photos, and People apps that initially debuted with the Consumer Preview.  Please reference the Windows 8 Release Preview Product Guide to see all new features within Release Preview.

Here’s some additional resources for you to review :

Windows Blog

Windows 8 app developer blog

Windows Store blog

Windows for your Business blog