This tool is being offered because an inconsistency was found in the Windows servicing store which may prevent the successful installation of future updates, service packs, and software.

I hope this doesn’t mean you cannot slipstream Service Pack 1 just like what happened with Vista.

Download details Update for Windows 7 (KB947821)

Download details Update for Windows Server 2008 R2 x64 Edition (KB947821)

Description of the System Update Readiness Tool for Windows Vista, for Windows Server 2008, for for Windows 7, and for Windows Server 2008 R2