That’s the theoretical limit anyway. In real life it’s unlikely that you’ll get download speeds faster than 100Mbps out of WiMAX 2, or the upcoming 802.16m stnadard. But you know what? I’d be pretty happy with 100Mbps.
WiMAX 2 will also be backward compatible with the current 802.16e WiMAX standard, which means you can probably continue using existing equipment to connect to the new network. That will make it relatively cheap and easy for providers such as Clearwire to upgrade.
WiMAX 2 probably won’t be finalized until late 2011, which means you probably won’t get your ridiculously fast mobile broadband until 2012.