The first 'service pack' for the HPC Pack 2008 R2 product is now available!
This update includes the standard reliability improvements that all of our service packs do, but it also adds several new features that you have asked for. Compute nodes can now submit new jobs to the cluster to enhance your workflow, cluster administrators can now create 'idleness' rules for bringing workstation nodes online, and one of the most visible changes is that you can now join Azure nodes to your cluster to increase productivity with several workloads.
The documentation on our technet site has been updated; it includes information on the new functionality as well as 'release notes' (including installation tips) that you should read prior to installing the service pack.
The single SP1 installer applies to all versions - the standalone Express and Enterprise installations, the Enterprise install that comes with the Windows HPC Server 2008 R2 Suite, as well as the standalone 'Client Utilites' and 'MS-MPI' packages. You can download it from the Microsoft Download Center.
An important note is that this service pack can not be uninstalled by itself. Uninstalling the service pack will also uninstall the HPC Pack itself, so you'll need to take a full backup (including the sql databases) before installation if you want to be able to 'roll back.'