Here is what is missing for me:
1. Sweat sensor.
2. Insulin sensor.
3. Smarter/more accelerometers to intelligently automatically detect what I'm doing. For example, if I start lifting 50 lbs in a dumbell bench press it should know that! My iPhone should auto update a fitness tracking app. If I start biking my normal "track" here in Toronto, it should automatically know that! So underwhelmed here.
4. No mention of emergency assistance "stuff", (like detection of heart attacks, or spiking insulin levels).
5. Some really stupid / weird features, although I do kinda like the shared heartbeat one. Would be fun on exercises / first date makeouts :)