I had an inside view of things, but all of the work being done is actually a long term roadmap towards building AR devices that don't suck. There many complicated issues to deal with, including batter life, processing power, input and control, heat management, placement of self and objects in a virtual world, safety, and on and on. That's all on top of figuring out what content is interesting and compelling.

Devices being made by these companies all embody elements of solutions to these challenges, but they all recognize it's a long road, and there's a lot of learning still to be done.