Repost:

The Remote Server Administration Tools (RSAT) for Windows 7 SP1 are now available for download. These include the latest version of Hyper-V Manager which supports both Dynamic Memory (DM) and RemoteFX.

Here's the link: http://www.microsoft.com/downloads/en/details.aspx?FamilyID=7d2f6ad7-656b-4313-a005-4e344e43997d