As soon as VP9 will be ready ;-). VP9, at the moment, doesn’t support one-pass encoding (and so even less can encode in real-time):
https://groups.google.com/a/webmproject.org/forum/#!topic/webm-discuss/alfjBJLIA3g
Note also that, for a remote display system, the encoding speed is much more important than the bandwidth usage. You can compensate for the lack of bandwidth in a number of ways. Encoding speed is a different kettle of fish. It’s a losing battle if the encoder takes 100ms to complete a frame. We have customers happily using MJPEG rather than VP8 or h264 because it is 2x faster than the fastest video encoder. MJPEG can easily saturate a gigabit LAN, but this is hardly a problem if you are on a gigabit LAN. Add to this that NoMachine must be able to support multiple user sessions running at the same time and you can see by yourself how speed is crucial. But this won’t be a problem for long. In few years from now all encoding will run on silicon, including VP9.
P.S.: NoMachine can use different streams at the same time. We have evaluated using VP9 for the frame refinements, since the visual quality of VP9 frames is vastly superior to VP8 and these refinements can be computed when the CPU is idle. At the moment it’s hard to say if this would bring a real improvement compared to a lossless refinement that can be computed and transferred in the same amount of time.