The main reason the comparison between JavaScript and Scheme is helpful is that it breaks the connection between JavaScript and Java. The first thing many Java programmers do when trying to write JavaScript is to try to create a class hierarchy (rather than using prototypical inheritance) using idioms from Java. Although possible, it ends up awkward and confusing in most cases. Understanding that functions are first-class and seeing functional idioms fall out from there is a big paradigm shift for Java devs.

Obviously JavaScript isn't Scheme using the author's "top 10 defining characteristics of Scheme." Crockford's analysis is on track - and John Resig and Bear Bibeault highlight the same idea by introducing functions are really fundamental to the languages more than objects (in "Secrets of a JavaScript Ninja").

The language's history does imply the comparison as well. Eich's original mandate was to "write Scheme for the browser" but he was later directed to give his language a C-like syntax and to ride on the coat-tails of the hype surrounding Java.

"JavaScript isn't Scheme" might not be accurate for folks schooled in the finer points of Scheme. It is very useful to those who cut their teeth learning Java.