True to previously announced dates, the first service pack for Windows 7 and Windows Server 2008 R2 is now available via Windows Update.

For Windows 7 users, the service pack offers little more than a roll-up of stability and security fixes. As is typical with Service Packs, some of these fixes have been previously released; others are being made available for the first time. Microsoft has a spreadsheet listing all the hotfixes and security updates within the Service Pack. Two new features are available to Windows Server 2008 R2 users: Dynamic Memory for Hyper-V, and RemoteFX. We've described these more fully in past coverage; Dynamic Memory allows more flexible memory allocation within Hyper-V, and RemoteFX enables server-side GPU acceleration for Hyper-V and Remote Desktop users.

In common with previous Service Packs, users with just a few systems will be better off using Windows Update; on an otherwise fully patched Windows Server 2008 R2 machine, the Windows Update Service Pack installation only needs to grab about 100MB of data. Those with more machines to update will prefer the 2GB standalone installer. Either way, a lot of free disk space is needed to install: up to 1GB for the online installation, and up to 8GB for the standalone installer.