Am one year late on this article but I had to chip in. I don't know what is more interesting, the main article by Joseph or the comments! Being a Kenyan living in Nairobi, am 100% immersed in the day to day transactions of mobile money. I love it. Don't know how we survived without it. As in IT entrepreneur in this field, I'd say the biggest challenge we have in expanding Mpesa's capabilities and taking it to fields unknown is Mpesa's service guarantees and network availability. I don't have the official stats but there are outages by Mpesa or connectivity to Mpesa which hinder any solution going fully fledged on Mpesa. It would be suicidal to build a solution that requires 100% up-time around Mpesa service. MNOs need to provide an SLA that is as good if not better than the Visa service. We need Safaricom to take responsibility -financially even by compensation- when a merchant is not able to receive his payment because Mpesa is experiencing delays or its totally out. Or introduce an offline version of it. How? I don't know. I sure would like to research on it. As I write we are working on a real time solution for the masses but we've had to put a work around that gives an option to write cheques and pay cash while ideally we'd have gone 100% automated on mobile money. Solve that and Mpesa (and its clones) will be ready for the whole world. Not just the third world.