Currently Being ModeratedOct 3, 2013 2:13 PM (in response to sjphotog)
You do not have much control over that.
You cannot prevent the export of the EXIFmetadata tags. They will be exported with originals or edited versions, since they are stored in the original image file.
When you are exporting original files, you can disable the export of IPTC metadata, for the edited versions these data will be included.
Also, in the Preferences > Advanced panel is an option, to enable/disable the export of location data with the images.
One way to prevent the export of certain IPTC data would be to simply duplicate all versions to exported, collect the duplicates in an album, and flag them,so you can easily recognize them again. Then batch change all duplicates of the image versions and erase the metadata tags that you do not want to export. Export the edited duplicates and delete them afterwards again.
This will only worrk for the IPTC tags; to prevent the export of EXIF tags you would need to clear the EXIF tagswith exiftool or a similar tool. Aperture will not allow to change them.