To explain why this case has so much attention is easy. When a story occurs of this nature the newpapers ask if the child concerned is 'of the faith' which means are they white, middle class and christian. Maddy was, therefore they heavily reported the case and in turn the TV news have to aswell.
The annoying thing about this story and the Alan Johnston story is that the news is being a blatant publicity tool by keeping the story in the news when they're aren't any developments. If they want to do that why don't they do it on a more important story such as Darfor. Politicising news, for whatever reason, is never good.