Mark Sullivan at FastCompany is reporting on a change that I definitely think is coming to the Watch at some point:
Apple will stick with the Watch’s current button configuration, with a button and a digital crown situated on one side of the device, but neither will physically click as before. Rather than reacting to the user’s touch by physically moving back and forth, the new buttons will vibrate slightly under the fingertip, using the haptic effect Apple calls the Taptic Engine. (The digital crown will still physically rotate to navigate through content.)
Makes a ton of sense to me, assuming it all works well when wet.