Well, you can't just endlessly edit your posts. All this stuff is meant to end up as an archive for everyone to get information from. There could be some serious holes in the helpfulness of these threads if things that we learned from kept changing (like how terrible threads are when all the pics get deleted or changed!)
I think the option to edit for the first day or so is only for the ability to fix typo's, bad links or incorrectly posted pics.
yeh, i didn't know what i was doing the other day and thought i'd be smart and delete my pics in my album , but i killed all my pics in my thread. nice move, fdp