Windows 7 + Windows Server 2008 R2

Microsoft just announced the availability of Windows 7 Beta which Is the next generation Microsoft Client Operating System, and also Windows Server 2008 R2 beta which is the next version of the Windows Server operating system from Microsoft built on Windows Server 2008

Windows 7 Beta or Windows Server 2008 R2 Beta can be downloaded using a TechNet Subscription or a MSDN Subscription from today onwards

More information on Windows Server 2008 R2

http://www.microsoft.com/windowsserver2008/en/us/r2.aspx

More information on Windows 7

http://www.microsoft.com/windows/windows-7/default.aspx