This plugin will let you sort the galleries by date and get info about gallery creation (and modification) date.
Please use at least version 1.8.3 of NextGEN Gallery. This plugin is not tested with lower versions
[ A T T E N T I O N ] NextGEN Gallery core modification required!
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NextGEN Gallery Date is an add-on for the best wordpress gallery plugin i have seen! With my plugin, you can sort galleries by date, show gallery creation and modificatio date inside gallery templates. It adds two new columns for gallery table:
added_date (on gallery creation)
modified_date (on gallery modification and upload of pics)