We just received rumored information from an insider at Apple that the Digital Crown, actually contains Touch ID hardware that can detect your fingerprint when placed on the crown. We have wondered why the crown has a dark glass like covering.
It’s likely that this has not been mentioned because software has not been completed for it to work seamlessly without problems. We expect if the rumor is true, software updates will enable the sensor.
BREAKING UPDATE: More confirmation from insider source that Digital Crown is Touch ID sensor: