Windows Server 2008 R2 Service Pack 1 beta starts, bits already leaked

The announced Service Pack 1 for Windows Server 2008 R2, which will introduce Dynamic Memory for Hyper-V and the RemoteFX technology (acquired from Calista in January 2008), is expected to be released within the end of this year by Microsoft.

Its official beta program started on June 21 and the first build already escaped the Microsoft Connect facility, probably hitting the illegal software distribution channels within the next 24-48 hours.
The documents accompanying the beta 1 are already circulating, and they indeed include confirmation of the two major features mentioned above:

Changes specific to Windows Server 2008 R2

Dynamic Memory
Constraints on the allocation of physical memory represents one of the greatest challenges organizations face as they adopt new virtualization technology and consolidate their infrastructure. With Dynamic Memory, an enhancement to Hyper-V™ introduced in Windows Server 2008 R2 SP1, organizations can now make the most efficient use of available physical memory, allowing them to realize the greatest possible potential from their virtualization resources. Dynamic Memory allows for memory on a host machine to be pooled and dynamically distributed to virtual machines as necessary. Memory is dynamically added or removed based on current workloads, and is done so without service interruption.
Virtual machines running a wide variety of operating systems can use Dynamic Memory; for a complete list, see the “Dynamic Memory Evaluation Guide” at [removed URL]. The guide also discusses Dynamic Memory settings and usage in detail.

Microsoft RemoteFX
Businesses are increasingly looking to leverage the efficiency and cost savings that can come from a virtualized desktop infrastructure. With the addition of Microsoft RemoteFX in Windows Server 2008 R2 SP1, a new set of remote user experience capabilities that enable a media-rich user environment for virtual desktops, session-based desktops and remote applications is introduced. Harnessing the power of virtualized graphics resources, RemoteFX can be deployed to a range of thick and thin client devices, enabling cost-effective, local-like access to graphics-intensive applications and a broad array of end user peripherals, improving productivity of remote users.
RemoteFX can function independently from specific graphics stacks and supports any screen content, including today’s most advanced applications and rich content (including Silverlight and Adobe Flash), ensuring that end users maintain a rich, local-like desktop experience even in a virtualized thin-client environment.
RemoteFX also adds mainstream USB device support to virtual desktop computing, including support for USB drives, cameras and PDAs connected to the client device. RemoteFX also provides a platform for hardware and software partners to enhance RemoteFX capabilities in a variety of possible host, client and network configurations.
To use RemoteFX, the virtualization server must be running Windows Server 2008 R2 with SP1, the virtual machine must be running Windows 7 Enterprise with SP1 or Windows 7 Ultimate with SP1, and the remote client computer must be running either Windows Server 2008 R2 with SP1 or Windows 7 with SP1. To connect to the virtual machine, the remote client computer requires an updated version of Remote Desktop Services (included in the service pack for all editions of Windows 7).