My wife has been organizing all our family photos using F-Spot for several years. After a long bout of inactivity, she started to work through the mass of photos that we have just been collecting and not sorting through. After she imported the pictured, she noticed that the date of the photos that F-Spot was reporting was off from when she remembered taking the pictures.

Well it turns out that F-Spot is indeed getting the dates wrong and is changing the EXIF header dates to be incorrect as well! A good summary of the problem is F-Spot Considered Harmful.

I think I'll take a look at digikam.