I think people might not understand exactly what these devices do. Iridium makes not just sat phones, but NSA approved secure sat phones. Their really big in the DoD, General Officers and some Colonels get Iridium phones so that they can securely communicate from any location and discuss secret squirl stuff. Companies use them for their CEOs and upper executives for the exact same reason. Of course the GO / CEO doesn't carry the phone around, their aide / personal assistance does, so the actual size much of an issue.
Now how will this translate into consumer space? I don't see the general consumer market as having a burning need for ultra secure personal communicators.