I've noticed this since I first got OSX. Every once and a while (not always), information on the desktop won't update unless you either click that item or the desktop.
For instance, if I delete a large file from my HD (I have item info on, showing the total space and how much is free) the free space won't update until I click on the icon.
Has anyone else noticed this? Just want to make sure I'm not crazy or anything...and if there's anything that can be done?