Got to play with one of the 13" touchbar models for a few minutes today at the store.
Damn. It's cool.
Tap-slide for volume & brightness; scrolling through photos; more and more that I barely got to try.
Switching text to bold, italics, and underline is VERY cool -- tap and it changes, and the "button" stays highlighted in case you wonder what it's going to type.
The font style buttons also demonstrate the purpose of the touch bar -- context-aware controls that are as easy to use as any other key, giving a visual indication of their status, and then disappear when they're not needed.
I want one. Such great potential, too. I'd love to see the prototypes and how Apple developed it.