What seems to be missing from this node about a traditional Japanese form of expression is some haiku actually written in Japanese. As pointed out by Perianwyr and WyldWynd, Japanese haiku are vastly different from English haiku - the following examples are from Basho, Buson and Issa.

ume ga ka ni
notto hinoderu.
yamaji kana

scent of plum blossoms
on the misty mountain path.
a big rising sun

kono aki wa
nande toshiyoru
kumo ni tori

why this fall (autumn)
I feel old
bird beyond the clouds

harusame ya
koiso no kogai

spring rain -
small shells on a small beach

mitesae samushi

looks cold -
to say the most
my shadow

Samples taken from the International Haiku Kim-dom at http://mikan.cc.matsuyama-u.ac.jp/~shiki/kim/kim.html

And one of my own, if only to provide contrast between good haiku and bad haiku (I'm taking liberties with Japanese grammar here...)

kono yoru ni
hito no kokoro wa
itsumo aku

in this darkness,
the hearts of men are
forever evil.

Now everyone who actually speaks Japanese can line up and kick my ass