Accounted for: The five mystery Vista updates to be added to SP1

Note: This post was updated on October 5 to clarify exactly what these Vista updates are and how they will be rolled out. 

When Microsoft finally rolled out the beta of its Windows Vista Service Pack (SP) 1 at the end of September, a new element of mystery was introduced. Microsoft officials said they were going to test simultaneously five additional reliability fixes that were not part of the SP1 beta -- but that the team ultimately planned to add into SP1 before it shipped in early 2008.

(While Microsoft's original posting to the Vista team blog made it sound as though these updates were not part of the Vista SP1 beta, this is not the case. These five are already in the beta. So if you are beta testing SP1, you've already got these five. If you are not a beta tester and you are using the Vista RTM bits only, these five will be new to you. In either case, these five updates will be part of SP1 final, Microsoft officials clarified on October 5. )

As of today, we now know what the five additional updates are. Microsoft rolled out one of them on September 27 and delivered the rest of them over the past couple of days. All are now available on the Microsoft Download Center. Microsoft also plans to push the five out independently, via Windows Update, at some unspecified future time, officials said.

The five:

• An MSXML Reliability Update (KB 941833, released to Download Center on 9/27). It is designed to resolves reliability and application compatibility issues in Microsoft XML Core Service 4.0 Service Pack 2, the Softies said.
• A comprehnsive reliability, compatibility and stability update (KB 941649). It addresses everything from battery life to startup time of the operating system.
• A fix pack for Windows Media Player 11 (KB 941651), which will "improve the reliability of Windows Media Player 11 for Windows Vista in certain scenarios."
• A USB update (KB 941600) which "resolves some reliability issues in the USB core components on the Windows Vista operating system."
• A cumulative update for Windows Media Center (KB 941229), addressing a variety of bugs in the Home Premium and Ultimate SKUs.

These five reliability and stability updates complement the two Vista mega-fixpacks that Microsoft rolled out this past summer. Those two were the reliability/performance pack (KB 938194) and the compatibility and stability pack (KB 938979). These two packs already are part of the Vista SP1 beta build Microsoft rolled out to 12,000 testers late last month.

Microsoft is still telling folks there's no need to wait for SP1 to deploy Vista. Even though Microsoft has been dilligent about rolling out fixes when ready, rather than holding them until the final SP1 due date, if I were an IT administrator, I think I would just wait for the final, catch-all update....