For the lazy, if you enter "correcthorsebatterystaple" the password strength gets set to "lol" with an info-box that reads something along the lines of "Don't take the webcomic too seriously. :)"
...but, oddly enough, not "correct horse battery staple" (at least, that's how I'm used to writing passphrases; I guess the comic could be interpreted either way.)
I find that message misleading. The xkcd comic does have a point, and thus should be taken seriously. (Despite the obvious downside that those passwords take longer to type, which is why I still prefer short, cryptic passwords.)
Its saying dont use that particular password. Any attacker of this script would know what it was inspired by and attempt that password in a dictionary.
Rendering it about as useless as 123456789 in this instance