Honestly, I think it's the least of our problems :)
Heh, but it's something that makes the menus feel fuller, and I enjoy doing it. :) (BTW: why did the "deselect" icon disappear? I realize my icons suck, but it seems they should stay unless _replaced_ by a better one...)
Frankly, I don't think all menu items need icons. Some of them are clearly secondary in importance or even temporary. Icons for everything just makes it look overloaded and noisy. I think if a group of commands (within horizontal separators) contains commands of different levels of importance, we should make an icon for the important one only. Otherwise it will be the same as making all of the text boldface, instead of just the key words.
As for unselect, I think it was particularly suited for having no icon, due to its meaning :)