As you may already know, Ubuntu 10.10 ditched F-spot as default photo organizer in favor of Shotwell. Now, Shotwell may be a better photo organizer than F-spot – I can't comment on that since I do not use any of these apps for organizing – it does have at least one very significant flaw that made switch back to F-spot.
Why do I need any of these apps if don't use them for organizing? Laziness, I guess. In Ubuntu 10.04 I found a very convenient way to do some very simple editing tasks such as cropping. If I opened a photo in Eog (Eye of Gnome - the default image viewer) there was a button on the right end of the toolbar called "Edit Image", which opened the image in F-spot. In F-spot I could do the cropping then save the image with all original EXIF metadata preserved. In Ubuntu 10.10 this "Edit Image" button opens Shotwell and I can do the cropping here as well, unfortunately, when saving the image all original EXIF metadata will be lost forever! From a photographer's point of view this is extremely bad and there should at least be a warning of some kind.
Fortunately I still had the original photo in my camera and no harm done.
Next I investigated how to replace Shotwell with F-spot as default editor for Eog. One would think that this would be configurable via the preferences. Well, yeah, sort of, if you call the gconf-editor a preferences dialog. I found a related post on the Ubuntu Launchpad where someone wanted to replace F-spot with Gimp. Basically the same problem and it also worked the other way around for replacing Shotwell with F-spot. After doing so I could safely uninstall Shotwell – No, it will not remove the "ubuntu-desktop" package ;-)