"Downloadable might be problematic for any one on a metered connection."

Partially true. When you consider how much time energy and effort goes into baking new content to HD, packing, shipping costs etc., a greener, faster and likely cheaper option would be to pay the guy at the "meter" for a day of unlimited fun and just download the chunks that are needed to be up to date.

Definitely not the case for everybody, but would be fantastic as an option.