While AT&T does not believe in Wi-Fi offloading (see "Wi-Fi Offloading - Booming in India but Failing For AT&T?" - here), Sarah Reedy reports to Light Reading that "KDDI Corp. has selected Ruckus Wireless Inc. to deploy more than 120,000 Wi-Fi hotspots throughout Japan, sources tell Light Reading Mobile. Ruckus will provide KDDI with dual-band 802.11n devices to blanket enterprises, starting in Tokyo in the small-and-medium size business sector.. KDDI plans to roll out 10,000 Wi-Fi locations initially in Tokyo then move nationwide with 120,000 devices by the middle of 2012, sources said"
See "Ruckus Makes Over KDDI With Wi-Fi Offload" - here. See below a short video from Ruckus explaining the advantages of "Carrier Wi-Fi".
"KDDI accelerated deployment following the earthquakes in Japan when a Wi-Fi public access network proved easier to set up than wireless, says a source close to the deal"