I asked my neuroscientist friend about this a few months ago and his response was that inserting electrodes and interacting with the brain is the easy part: preventing the body from rejecting them or forming scar tissue over them after a few weeks is the hard part that nobody has been able to solve yet.
Ah, well that is exciting then (I did watch the video and know they said the pig had the unit for two months, but I wasn't sure if they had actually solved it or not, although two months is certainly a great sign).
