for the feeds in yahoo site explorer .. does yahoo automatically check them whenever they are updated like google does .. or do i have to resubmit them everytime something changes so that they are processed?
You have to update them everytime I think, I do. This prompts a search or ping to the SE and it is forced to take action. If left on its own it would probably depend on the number and quality of links. So a resubmission would do the trick.