I was thinking about that too. Imagine having image recognition within the headset or glasses which can draw boxes around items and match them against a global database. One could be walking around and see something interesting, then press a button or say a phrase to query it for information right in your glasses.

A lot of infrastructure and data would be needed before it reaches a critical mass and mass adoption follows. The more people using it, the more data there is in the system, the more people want to use it.

Another really great feature would be captions for conversations going on around you - a big help for the hearing impaired, and maybe even helpful to ordinary people to keep better track of the conversation flow.