In a report on the regional economic outlook for Sub-Saharan Africa, the IMF describes M-Pesa as a "resounding technological innovation".
The report observes: "M-Pesa now processes more transactions domestically within Kenya than Western Union does globally and provides mobile banking facilities to more than 70 percent of the country's adult population."
Although deeply entrenched in the local economy, M-Pesa has yet to replicate its success in the cross-border remittance market.
This may be about to change. In March, M-Pesa operator Safaricom sealed a deal with Western Union to use the network's backbone as a processing hub for receiving transfers from Western Union's 80,000 agent locations worldwide.
The expansion of the service globally followed the successful debut of the offering from Western Union Agent locations and the westernunion.com website in the UK.
According to the Central Bank of Kenya, Kenyans living outside their home country sent US$642 million home in 2010 - up from the US$609 million sent home in 2009.