Does anyone know why the PageData.Changed does not update when saving or publishing a page? It looks like it might have been superceded at some point by PageData.Saved but it is still used when you hover over a page in Edit mode.
you have to check the checkbox 'Mark Page as Changed' for this to take effect this can be found within the Settings tab
Code for doing this programatically can be found here
If you allways want the date to be updated when the page is saved, why not use CurrentPage.Saved instead?