General opinion seems to be they did not want to say anything about battery life as they know it's bad.
You speak about the positive aspects of your device, you keep quiet as much as possible about the negative aspects of your device.
Obviously they are going to have people working on this very issue right the way up to the last moment, so that when they DO publish battery life, they know they've made it the very best they possible can for the very 1st model out the door for early 2015.
They will have people working on optimizing every dam tiny little thing, stopping anything running they possibly can, that really does not need to be running.
As they phone it needed, the watch can be almost dead until it's woken up and pulls data from the iphone.
It would be nice to think they are going to amaze everyone, and they've optimized it so much that it blows all other similar devices away with it's battery life. that will mean everyone else will have to up their game also, and be good for all consumers of all products