This is an early concept video that was made when Project Glass was just getting started. While a lot has changed since then, our motivation to get technology out of the way remains the same.
( Source: YouTube.com | Project Glass: One day... )
"...get technology out of the way..."
I don't get that feeling when I'm reading / watching reviews of Google Glass. And I don't think a watch would be any better.
Can you imagine someone staring at their watch every few seconds / minutes, checking the latest notification? What type of signal does that send?
But, what about headphones? They aren't obtrusive and most people know when you have them on, you are doing something else. If they were in-ear headphones, with bluetooth, you might interact with them much the same way you'd theoretically interact with Glass or a watch.
There just wouldn't be any technology in the way.
There might be a bit of confusion if you are talking to Siri via the headphones and someone is nearby, but that's nothing new.
Walking uptown this morning, I was using Siri to capture some thoughts and ideas. It worked generally well (using a pair of LG bluetooth headphones) but I was wishing it would work both ways. Realizing I had my headphones connected, it would be great if Siri cut into my music and told me about my day, any tips based on my location, any VIP emails that have come in, etc.
I do think Apple will get into the wearable technology craze but I don't think it's a watch - I think Apple's next big thing is a set of headphones that interact with your iPad / iPhone / iPod.