Just as support for one Service Pack ends, Microsoft has announced that the first public beta of Windows 7 SP1 is now available. Revealed at the company’s Worldwide Partner Conference, a beta version of Service Pack 1 for Windows Server 2008 R2 was also unveiled.

The software giant is preparing the first major update for its flagship OS even though it has only been on the market since last October. However, don’t expect too many changes. According to the official Windows Team Blog, “SP1 for Windows 7 does not contain any new features specific to Windows 7”, but is simply a collection of the fixes already available through Windows Update as well as a few extra hot-fixes.

While it might seem odd to announce a major update that doesn’t contain any actual updates, the release of a Service Pack is a significant milestone in an OS lifecycle. The good folks from Redmond will no doubt be hoping that SP1 will convince corporate IT departments to finally move users away from Windows XP-based systems. Many will see this Service Pack as an indication that the OS is genuinely stable and ready for full-scale deployment.

Alongside the desktop announcement, the beta of Windows Server 2008 R2 SP1 is also available. This release includes a few more substantial changes, with dynamic memory for virtual machines and RemoteFX desktop virtualisation being the major highlights. Full details on these new features are available from the Windows Server blog.

For those interested, the beta versions of both Service Packs can be downloaded from TechNet now (registration required). However, since there are no major updates for the desktop user, we’d suggest leaving this one to those working in corporate IT departments. For the rest of us, Windows 7 SP1 is expected to be available in the first half of next year.