Thank you everyone, some genuinely useful and informative posts.

In common with a lot of the populace of this forum, I work with, associate with and count myself as one of, those folks who would feel like they'd lost a limb if they had to use a handset with no data service available. I guess the fact that I was scratching my head to come up with a compelling use case for MMS serves to illustrate how much I'd been taking this for granted.

Who knows, maybe I should even try sending a few! But then again, MMS'ing the same picture to 6 or 7 contacts, versus one upload to Flickr...