I'd like to migrate my photo library out of Aperture, but still use it to edit photos (maybe). I'd like to export the masters and the modified versions of all my photos into standard Finder folders in the format YYYY/MM/DD. I can't seem to find any advice on how to do that.
I have been looking for a solution for you
I think its a two pronged approach - you can export the files using this guide.
Then you can use Amok Exif Sorter which is Mac compatible http://www.amok.am/en/freeware/amok_exif_sorter/
I agree with Rob that a two-pronged approach might be easiest. He suggests specific software, but it an actually be generalized:
For example, you can use the free, cross-platform command-line tool
This will take all of the
Pretty much any bulk rename tool will work — if you're comfortable with the command line, jhead is an easy free choice. If you're looking for a GUI option... take your pick.