F-Spot isn't too good for spontaneous needs, having to import stuff etc, and its viewer isn't much for organizing.
gThumb does all of these things well (even organizes video clips) whilst keeping it simple, and it has a small footprint. Why confuse the average user with F-Spot!
Make F-Spot go away from the default install the same way as with the GIMP. People who need it will find it, otherwise gThumb with its easy-to-understand UI is the way to go.
Link to the idea on brainstorm: http://brainstorm.ubuntu.com/idea/22673/