I fail to see what this offers that the other products in this space doesn't have. At least hardware-wise.
A set of new UI primitives and the hardware to support them (crown thingy, tactile feedback chip).
I have doubts about the crown thingy -- turning a watch crown while the thing is on your wrist is quite uncomfortable. I understand it's a big crown, but still doesn't seem ergonomic to me.
More like half a generation (if that). And by the time it ships, the lead in tech will be all but gone.