So, this doesn't seem to be documented anywhere, or I just missed it, but everything I read about RemoteFX deals with VDI and VM's and Hyper-V
While I was configuring a windows 8 ent VM on my Hyper-V server (with a Geforce 460) I noticed that if I directly RDP (rdc 8.0) to my Windows 8 Ent physical machine (with a GeForce 670GTX) it was actually connecting using RemoteFX (saw an entry in the event logs on the remote machine, on the line of "connetion using remoteFX guest mode). When I connect to my VDI VM, it says "connection using remoteFX host mode".
Can anyone confirm, cuz just connecting to a physical box via RemoteFX is pretty cool.