Paul, I think the original poster should be able to remove a posting. An example would be for a short term question or something with a time limit or something for sale. This might cut down on the mass of things being stored. Just a thought
It gets a little messy with replys and all to actually delete a post. Storage isn’t an issue at all. One photo will equal a months worth of posts :). Each post can be edited by the poster, and that should help on the expired items.
Maybe we’ll have a delete that just clears the post and display it as deleted by <user>