Jesus, these comments are so pessimistic. As of now, the three top-level comments are "Wouldn't this cause headaches?", "Wouldn't these have a uselessly small viewing area?", and "Wouldn't these be too blurry?". Come on, people; have some imagination. These aren't even show-stopping physical limitations (which humanity has sidestepped thousands of times before); these are relatively minor engineering problems.

Even as someone with essentially no experience in this area, I can think of a few potential solutions to the complaints thus far. The eye strain and focus issues are solved by using pre-collimated laser light instead of LEDs. Our fabrication isn't quite there, but again, it's an engineering challenge. The viewing area size is expanded by eye tracking (possibly via sensors in the contact lens).

It's good to question these sorts of things, but at least start with interesting questions!