Yes, of course, there's a LOT of possibilities for a vapor product.
Eye strain is a very real possiblity. 3D tech generally has that reputation. Use it for long and your eyes suffer. This very well may have the same issue.
Others might push harder: this may blind us from using it for 10 minutes. It might radiate our brains. Over-immersed morons in Goggles may walk right into traffic and be killed. "We" can imagine any number of negatives about an unknown anything.
As the Apple "think different" crowd though, we can also imagine any number of positives if we try. Maybe it improves our vision? Maybe it smartens our brains? Maybe the cameras saves us for accidentally stepping into something oncoming the two eyes on our face would miss without goggles.
A virtualized monitor could dynamically float to any level, any angle, etc for ergonomics. On the other hand, will the neck muscles tire of the added weight. Will the brow sweat from the contact? Will we have impressions of goggles in our skin when we take it off? Will- like diving goggles- the lens fog up when worn in certain conditions? Etc.
Thousands of questions with very negative connotations and very positive connotations float in collective imagination. We have no answers today. Just guessing & speculation. Lots of answers are a few weeks away and then many more at some point thereafter when these make it out of the lab. Then, we'll finally know what this is, what it costs, what it does, what it can't do, negative issues, positive issues, etc.