After a long wait, I've finally integrated @xvidun's feature of automatically placing images on a MapKnitter map if they have GPS EXIF metadata -- that is, if they've been taken from a smartphone or camera with a GPS. I implemented only placement in latitude/longitude so far, but we should be able to expand this to figure out rough compass heading and altitude with a bit of extra work.
To use this new feature, just drag images which have GPS EXIF data in them onto a MapKnitter map, then click "Auto-place with GPS". MapKnitter does the rest!
Watch this video to see it in action, or try it yourself: