Re: Personally
"Just imagine having a room with an invisible touch sensitive sensor instead of a clearly visible light switch."
I know EXACTLY what you mean.
I'm currently working on a project that has 'an interface' that requires users to do something specific with it, in order to control the device (while simultaneously rejecting 'accidental' activation of the user interface). However, the amount of feedback that could previously be given to the users [to help them 'get it right'] was inadequate. I recently fixed this, after making some architectural changes to support it (priorities, priorities), so that the feedback was a LOT more intuitive (and gives more information to the user to help him use the interface). NOW it's much easier to use, and hopefully will be acceptable to the end-users. That's the goal (usability).
So yeah, it's extremely important for the UI to be as intuitive as possible. Otherwise people will have a hard time using it, and are likely to complain or "just not use it".
And, naturally, any influence I have over web design, icons, etc. WILL contain more 3D skeuomorphic and veer away from the 2D FLATSO and 'hamburger' menu. And I'm passing a link to the article along to "the powers that be" to help justify it.