This is a great tool! I had been looking for a freeware tool to modify EXIF image data and stumbled across this. I had to install Perl for it, but that was easy too. Due to my lack of Perl ability I have a Python script which calls Perl to run ExifTool!
Could do with a "quiet" option for running in batch mode (all those "1 image changed" messages is untidy).
Wow! Less than a day after my review a quiet option appeared. Thanks Phil - you deserve a 5/5 for responsiveness!