Its interesting how much technology they pack into a small device - 1 GHz CPU and 4GB flash, camera, gyro. The screen is 320 x 320 or about 6x20 characters. Google glass is same height, but twice the width. mini-Linux, Android and Java.
Overall I see good potential as a basic messaging receiving device. I am dubious about the camera, because it is hard to aim unlike a smartphone or glass.
The basic user interface follows smartphone conventions- touch activated and scrolling cardlets. The positive is that you can write a similar applet for both a phone and watch. I personally dont think the long term future of a smart watch is as a small smartphone. Other user interfaces such as voice and wrist guestures will be more efficient.
The first two generations tether with smartphone for internet access. Ditto google glass. Battery life is about 3 days if you dont use the camera or video.
Samsumgs million dollar smart watch app contest (top prize 100K) ends this week.