A few days ago, Microsoft posted on their B8 blog that work on Windows 8 RTM is on and the company will soon finalize it for the release to manufacturers. Windows 8 RTM will feature the new desktop look.
Microsoft is trying to metrofy the look and feel of desktop by giving it a metroish theme.
According to Winunleaked the latest RTM build number is
A few days ago, Microsoft had confirmed that Windows 8 Pro upgrade from XP, Vista and Windows 7 will cost $40.
This price will be applicable only when you upgrade through the Windows 8 Upgrade Assistant. The Packaged DVD version of the upgrade to Windows 8 Pro will cost $69.99.