Forum Moderators: open
The folders/directories themselves aren't changing (such as being renamed or moved to a different part of the folder tree), correct? So why would their last updated date change? The CONTENTS of those folders, the files contained in them, are what's changing; and that's what the spiders are interested in.
As long as your site's pages are interlinked well -- meaning every page you want the spiders to slurp up is linked from some publicly accessible page on your site -- the spiders will find your new files with no problem.
