I'm an extreme multitasker with a multimonitor setup. I'm constantly ALT+Tabbing between apps and OPT+Tabbing between windows.
To see which app is currently frontmost, I have to look at the upper-left corner of the menubar on each of the monitors to see which one is not greyed out and the app name. Besides being an ergonomic annoyance, sometimes I will confuse myself for a second and switch to another app / window despite the fact I was already on the correct app / window.
Anyway, If I could glance at the touchbar to see the current app ICON and/or NAME and/or FILENAME, I wouldn't have this issue.
I figure this would be pretty easy to implement given the recent addition of the Dock Widget.
What do you say?