So today's big news is that Windows Vista SP1 is due out before the end of 2007. So why has Microsoft been trying to keep this quiet? Well, because they don't want SP1 to unnecessarily hinder the adoption of Windows Vista. I say unnecessarily because the mentality still exists that Microsoft products aren't worth upgrading until the Service Pack comes out. But with Vista, that's simply not the case. Vista is without question the most consumer-focused release Microsoft has ever done, mostly because more testers gave Microsoft feedback than in any previous release.
So why will they have SP1 ready this year? Because Windows Vista and Windows Server 2007 share the same codebase, which means both operating systems use many of the same binaries. While Windows Vista has gone through more reliability testing than any previous consumer OS, Windows Server 2007 will have an extra 6-10 months of testing. So Microsoft gets a two-fold benefit for the extra WS2007 testing this year.
The end result is that Windows Vista SP1 will have the same stability, security, and reliability as a server OS. This cannot be understated: Microsoft has never had server reliability on the desktop before. Windows Server 2003 has been a rock-solid OS from day one, and the number of vulnerabilities have been far fewer than previous releases. Since Windows Vista started from that codebase, you already have a really stable OS. But to have the same bits running on both desktops and servers can only mean good things for consumers moving forward.
So while it's the first time in Microsoft's history that the first Service Pack has come out the same calendar year as the first release, don't take it to mean that Vista is more buggy or less stable than it should be. It just means that the Vista will get to reap the benefits of the additional Server testing that is going on as we speak. Which is why I said earlier that if you want to still have an impact on Vista after RTM, get on the Longhorn Server beta.