The IEEE standards body has released a draft for 802.16m which specifies 1GBit over the air WiMAX and 100MBit in "high mobility" mode. It is also apparently backwards compatible with 802.16e. We won't see any hardware with this draft specification for at least a year or two, but it looks promising.

The high datarates are achieved by utilizing MIMO technology, the same wizardry responsible for the higher throughput in 802.11n.

More information on things to come over at Daily Tech.

You can also find a draft of the specification on the IEEE Website.