Im not sure how you missed my point, so i guess i'll have to carefully outline it for you.
You said it would be difficult for iPhoto to keep track of changes made via finder. Its not difficult to keep track of changes made in finder. Picasa keeps track of changes made in Finder. Google gets paid a whopping 0 dollars for every download of Picasa, and yet they can pull off an app that scans a folder for changes. Must be very complicated
Then i compared iPhoto to iTunes because they both share the distinct ability to be oblivious to what Finder does. Neither includes the basic ability to scan the media folder for changes like Picasa, Winamp, WMP, wxMusik, MusikCube (just to name a few that i have personally used).
Do you understand now or do i have to (figuratively) speak slower.
Oh crap, your mind will probably explode from trying to understand that phrase, just ignore it.