I'm hesitantly excited about this language, after reading this article. The power increase I've gained going from an "OO" imperative mindset to functional has been huge. The simple volume of code from other styles just boggles my mind. I can't understand why people prefer their verbose code with so much edifice. Making another leap like that sounds very promising.
At the same time, it does sound slightly off. What's the catch? In the text editor example, how capable is it? Often, such claims rely on a trick, like saying "<textarea/>" is a text editor in 11 characters. Or the tiny Haskell quicksort that's actually rather inefficient.
I think I'll try playing with it. How long should a Logo interpreter in K be?