This explanation is fascinating to read. I do use Dreamwidth's image hosting, but it *is* cumbersome, so sometimes I put the pictures up on Flickr and copy them from there. Flickr so far has been long lasting (despite changes in ownership), but you're right, eventually things do seem to disappear (or become unusable). I had no idea that people exploited images in the way you mention--actually, do you know what it is that a bot does? Is it that it somehow is able to replace images in undefended storage areas with different images? (How awful, if so.)