[cromwellian]

I highly doubt they will "pack features into the glasses". If I were to guess, they will pack them into a smartphone platform which communicates with the glasses over bluetooth. That is, the glasses will be a peripheral of the smartphone.

Also, nothing they showed was very exotic. Google already has walking navigation. Google already has Hangouts, Screen Sharing. Google already has Goggles image recognition. The only 'sci fi' element was the always-on microphone handling Siri-like queries. They could have showed a lot more crazy stuff: face detection, augmented reality tracking, augmented reality games. They didn't show anything that isn't technically possibly to achieve. It's rather mundane if you think about the features they showed as applications on your phone instead of displayed on your eye glasses. The only thing different is the input/output device.

Apple announced the iPhone 6 months before you could buy it. The initial version didn't do much beside fixed functions and Web browsing. It wasn't until the App Economy that it's potential was unlocked. People speculated for months about app development only to be told much much later that there was none. People speculated over flash. Over Java support. MMS messaging. In fact, I have an old post from 2007 exactly discussing all of this naysaying due to speculation: http://cromwellian.blogspot.com/2007_01_01_archive.html

I think Google has actually put forward a very pragmatic concept video that is fully realizable, albeit with latencies and delays and voice recognition accuracies that don't quite match up to the real world (but even Apple commercials show apps serving up answers faster than they do in reality)