I'm totally with skipvia: even ordinary monosyllablic words have a purity about them which has to be worth something. Short words tend to have plural meanings and, because they denote basic things or ideas, lend themselves readily to metaphor.
As far as I'm concerned, a given two-syllable word has to be twice as good as a given one-syllable word in order to have the same amount of value.
That the only four to make the list should be, as Jenn notes, lubricious, is further disheartening.
Short words have more power than long words. Take the ubiquitous pneumono...osis. It's a sentence all by itself, and a rather long one at that. Why not just say "lung disease?" (I realize that science needs words that provide a high degree of specificity, but we don't often use them in conversation.)
I am particularly drawn to short words used metaphorically. Phrases like "his elevator doesn't go all the way to the top" convey so much meaning with such simple words.