Service Pack 1 will be released within the first half of calendar year 2011 according to a post on Technet, Windows 7 and Windows Server 2008 R2 Service Pack 1 Beta Frequently Asked Questions.
Windows 7 Service Pack 1 is an update for consumers and IT Pros that helps keep your PCs supported, provides ongoing improvement to the operating system, by including previous updates delivered over Windows Update as well as continuing incremental updates to the Windows 7 platform based on customer and partner feedback, and is easy for organization to deploy a single set of updates.
Windows Server 2008 R2 SP1 is an update for enterprises and IT Professionals that includes virtualization enhancements, previous improvements delivered via Windows Update, and addresses feedback from customers.
Download Beta for Service Pack 1
The beta of SP1 can install on RTM evaluation versions of Windows 7 and Windows Server 2008 R2. You can download Windows 7 and Windows Server 2008 R2 Service Pack 1 (SP1) Beta.
For more information, see Windows 7 and Windows Server 2008 R2 Service Pack 1 Beta Frequently Asked Questions.
Bruce D. Kyle
ISV Architect Evangelist | Microsoft Corporation