I have just switched back to a Mac as my primary computer after a hiatus on a Vista PC. I like iPhoto for a number of functions, but I also prefer Picasa for a number of others, particularly the ability to view and manage photos in pre-existing folders on my hard drive.

In fact, I hate how iPhoto organizes your photos into numbered folders with relatively little meaning. I hated it on my old iBook and I still hate it on my new MacBook Pro.

With Picasa on my Windows machine, I had organized all my photos into folders that are name by event/occasion/etc. and sorted in larger folders according to event type and other things. I've now moved all those folders over to my new Mac.

I would like to be able to use both Picasa and iPhoto to manage and edit my photos. When I make changes to files and save them, or delete photos, it makes those changes directly to the folders and files where they are on the HD. Yet in iPhoto, even when I use referenced mode, if I delete or edit a photo, it doesn't make changes to the files in those folders, it saves them in the "Preview" folder in the iPhoto Library. This is enormously frustrating.

Does anyone know if there's a way to make iPhoto work in a true reference mode, in the same way Picasa does? Why is Google's product so much more interoperable than Apple's?