I think a lot of people got burn when they adhered to the "i want to use just this thing for everything" mantra, which is pure illusion. And as with all illusions we tend to nurture, it will lead to a crash with the status-quo of reality.
This was also what happened with Javascript. If you used it as the script language that it is meant to be, everything will be fine.
The problem, as i understand it, is trying to follow the misguided and over-hyped steps of Java.