Finally Microsoft has announced the availability of public Beta version of SP1 for Windows 7 and Server 2008 R2 at Tech-Ed conference.
According to Microsoft:


The public beta of Service Pack 1 for Windows Server 2008 R2 and Windows 7 will be released by the end of July.
SP1 will be a joint release for both Windows Server 2008 R2 and Windows 7.
SP1 will not contain any new features that are specific to Windows 7 itself. For Windows 7, SP1 will simply be the combination of updates already available through Windows Update and additional hotfixes based on feedback by customers and partners.
From the server side, two key new features have been included:
Dynamic memory is an enhancement to Hyper-V in R2 and allows IT administrators to pool all the memory available on a physical host and dynamically distribute it to virtual machines running on that host as necessary. That means based on changes in workload, your VMs will be able to receive new memory allocations without a service interruption.

RemoteFX is the latest addition to Microsoft’s desktop virtualization stack. Using this new feature in Windows Server 2008 R2, you’ll be able to deliver an even richer and more user-transparent desktop virtualization experience. RemoteFX functions independently of any graphics stack and supports any screen content, including rich content like Silverlight or Flash. It also enhances the end-user’s hardware experience with support for USB redirection. Because it uses virtualized graphics resources, RemoteFX works on a wide array of target devices, which means you can deploy it over both thick and thin client hosts and a wide variety of network configurations
DLow Reviewed by DLow on . Windows 7 and Server 2008 R2 Service Pack 1 (SP1) Beta Coming in July 2010 http://www.imgcafe.com/uploads/windows7lo.png Finally Microsoft has announced the availability of public Beta version of SP1 for Windows 7 and Server 2008 R2 at Tech-Ed conference. According to Microsoft: Rating: 5