This same procedure can be used to export selected photos (not in a journal)--as you might want to do with photos you edited.

When I went to my iPad's Apps -> File Sharing section in iTunes, iPhoto was not there! This meant I couldn't access the journal I had just exported.

Actually, iPhoto was not the only app missing from File Sharing. Garageband, Keynote, Numbers, and GoodReader were absent as well. I had never noticed this before (although I rarely check this list, so who knows). Adding to the mystery, after ejecting the iPad and/or quitting and relaunching iTunes, a different subset of apps would typically appear. For example, on the next occasion, Garageband and GoodReader returned, but Pages was gone. Very odd!

If I kept trying, iPhoto would eventually show up and I could complete the export.