RDP8 also supports RDP over UDP which further enhances performance in high-latency scenarios. I'm assuming that is also not factored into that claim either
I kept waiting for the demo video to show any streaming video which they kept avoiding. VNC is ancient by industry standards. While this is convenient and the open license is helpful, there are far more mature remote desktop protocol stacks available commercially. PCoIP, RDP8, ICA/HDX, heck even HP's RGS cam handle streaming video and USB remoting.
In early 2013, guacamole would do video for a little bit, and then get desynchronized from the server. It would be pretty great while it lasted though...