That said, I could really see glass taking off in occupations that require field work - for example, a surveyor or construction foreman can use them in the field and managers/architects/engineers can review pictures and video of project progress or problems that might crop up in the field. It could be attractive to certain consumer markets like cyclists, etc.
Similarly I could see Glass being adopted wholeheartedly by military, security and police personnel, especially as replacement for military helmet cams.
All my opinion of course. We certainly live in interesting times, and kudos for Google for trying to expand our horizons.
edit: BTW if the developer preview were available to non-IO attendees, I'd seriously consider getting one. Like I said, it would be extremely useful during field work.