On digg I just found an article that compares digikam, f-spot, imgseek, gqview and picasa. Except for digikam I have tried all the programs for myself and am currently using both gqview (for the occasional image viewing) and f-spot (for really organizing photos).
As mentioned in the article f-spot wants to organize all your photos by date. I don’t really like that myself but disabling the copying into a special fspot-folder does not work. I hope this will be fixed soon.
I don’t really see why gqview is included in the article: I think it is only an image viewer and not a photo organizer. But anyway, the article is worth a read.

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