Dear Haikujane,
I'm wondering why you feel it is so important to hold so closely to the haiku form of ending with a noun vs. a verb (reading your comments from the soap box on your web site).  I agree that form is important but what about sound and rhythm, as well as the notion that Haiku (and all poetry for that matter) allows for a measure of movement and change within its historical tradition. Doesn't language become brittle when structure takes over all of its other elements? Freedom in Canada

Dear Freedom,
Because haiku are so short and pointed, we usually make an effort to drop all adjectives and adverbs unless we really need a modifier to add to the depth of the linkage between the images and the inspiration. In Japanese, as well as in English, there is an avoidance of ending a line (or a sentence) with a preposition. So this rather leaves us, in English, with having either a noun or a verb as the last word of a haiku.
Because haiku is a direct descendant of the form known as renga, it still carries some of the four-hundred year old rules. One of these archaic rules, that some of us still follow is: the third link in a renga (the daisan) should end with a verb. Thus, to give this link its honor, the others need to end in a noun to set off the one with the verb ending. The reason it had to end with a verb was to cause a “carry-over,” hooking it more securely to the following link. This was intended to capture the reader’s attention and not let it go by forcing the mind to want to know the object of the verb, which was found in the next link.
All of this is well and good and rather ancient. My personal gripe with haiku ending with a verb, in English, is because it often is the result of the author being too lazy or not inventive enough to create a third image for the haiku. An example would be:

a spring day
the young girls

Skipping what? School? Home? Lunch? Rope? Stones? Hopscotch? I feel a better haiku would result if one put “skipping” up on the end of the second line (where it feels like it belongs) and added the third and final image. It takes some work to find the exact thing young girls would “skip” that expands the concept of a spring day. Here is the work and the genius.
As with any of my “rules” and opinions, this does not mean that every one (or even I should ) always obey them. But looking over the masses of haiku written, I think you too, will find that  the majority of them end with a noun. Still, when your haiku asks to end with a verb, and you have the three needed images, why not let it make itself special and different. Go for it. I agree with you that too many rules can make a form brittle and bottled. That is why I advocate changing your own rules often – like socks. Blessed be! \o/ Haikujane