Dear Beta Tester:
This is the second phase of the beta testing for the Windows Package Installer (Update.exe - v6.1). We have received tremendous amount of feedback from the first phase (October 14) release of the beta project. Thank you very much for your participation and quality work!
The Windows Sustained Engineering team is planning to release a newer version of the Windows Package Installer (Update.exe - v6.1) representing the installation technology used for service packs, updates, update rollups, security updates, and security rollups for Microsoft products.
News source: Beta Place