Thanks, I appreciate you took the time to test your set and reply with your results. I had read about which devices support 3D through open connect, but I've never seen any documentation specifically stating the max bitrate supported by the LG Netflix app. The supported 3D devices might be the only LG devices which support the higher bitrates/superhd. Hopefully someone else will chime in and we can find the answer.
Here is the SuperHD page on Netflix:
It points back to the 3D support article I linked above for a list of compatible devices so I assume the technology (hardware\software combinations) are tied in with eachother (SuperHD and 3D).
That still doesn't explain my weird kbps issue. 3000 kbps max with the LG set and 3850kbps with my Sony BDP-S590. (Both are wired through the same switch and router)