Clearly, that wouldn't do at all. Having a permanent LJ account, I have a metric ton of space at Scrapbook -- and that even allows me to use the same security settings as I have on my Journal. That certainly allows me to take pictures that not everyone can see, which offers more opportunities to post 'em.
Having found a Python module to upload an image to Scrapbook, all that was needed was to write some glue between some modules to retrieve an email from a particular email adress, resize the image, take into account some special codes to set security, tags, icon and mood, and then use the Benzaiten code to post an Entry that links to the image.
Took me some time to get it all right, but now I have a scheduled task that does just that. As long as Calcifer is running (and it's always on), any photo I mail will be posted within five minutes. There is now no more reason to use mobypicture.com anymore -- all is now in one place!