Many tend to forget that the same day the Windows 7 beta was released, the Windows Server 2008 R2 beta went public as well, and the same goes for the Windows 7 Ecosystem Readiness Program. The media is letting Windows 7 overshadow Server 2008 R2, but Microsoft isn't taking much notice. As with any Windows Server release, the software giant is eating its own dogfood: the company recently finished rolling out the operating system on its homepage, though it's not clear which build the company is running. Netcraft spotted the change:
Microsoft is now running Microsoft-IIS/7.5 on its main website Microsoft Corporation. IIS 7.5 is part of Windows Server 2008 R2, which is currently in beta testing. The changeover appears to have started around the 8th January, when Microsoft Corporation began responding sometimes with Microsoft-IIS/7.5, but with many requests still being served by 7.0. Now the transition appears to be complete, with all requests now being handled by version 7.5.
Full Story: Microsoft.com moves to Windows Server 2008 R2 beta - Ars Technica