I had the same reaction. Even though I grasp scientifically what they do, seeing that video is an almost spooky experience.

I know it cannot be used to visualize what we dream/hallucinate yet, it only shows what the patient directly sees. But if that's the next step... wow, it would change communication and content creation as we know it if we could just dream up videos in our mind and upload them :-)

The potential that we could one day share exactly what we see in our imagination is so awesome, it's almost hard to imagine it! (Irony not really intended)

And what about "uploading" yourself to a computer. What happens if one day we can create exact copies of a person in silicon?