A: Software Assurance customers have access to Windows Fundamentals for Legacy PCs (WinFLP), which is a special version of Windows XP designed to run on basic hardware configurations. It was primarily used to turn old machines into thin clients that could then connect to other services using RDP.
Windows Thin PC is a replacement for WinFLP, provided as a benefit for Software Assurance customers. It's a thin OS based on Windows 7 that's locked down and really focused on repurposing devices as thin clients. The good news is that Windows Thin PC is based on Windows 7 SP1, so it has support for RemoteFX. Also, because it's based on Windows 7, it can be patched and managed using existing System Center Configuration Manager and Windows Server Update Services infrastructures. Normal management, remote desktop clients, security applications, and media players run on Windows Thin PC, but you can't run productivity type applications, such as Microsoft Office.
Hardware recommendations for Windows Thin PC are similar to Windows 7: 1 GHz processor, 1GB of RAM, 16GB of disk space, and ideally, a DirectX9 graphics device with a WDDM 1.0 driver and a bootable DVD-ROM drive.