I primarily use Detexif to quickly show me the dimensions and colour profile of an image. Scrolling down I get information about the camera and settings, and finally a map of where it was taken (for images with GPS coordinates).
Im taking off one star because having to scroll windows up and down to see all the information slows me down considerably. It would be nice to be able to collapse sections by default (I would collapse the Camera and Shot sections if I could, as I don’t usually care about this information) and it would be nice if Detexif remembered the window size when I drag it bigger. That way I could see the map without having to scroll down to it.