Here's a statement from the ITU from their December meeting:
Following a detailed evaluation against stringent technical and operational criteria, ITU has determined that “LTE-Advanced” and “WirelessMAN-Advanced” should be accorded the official designation of IMT-Advanced. As the most advanced technologies currently defined for global wireless mobile broadband communications, IMT-Advanced is considered as “4G”, although it is recognized that this term, while undefined, may also be applied to the forerunners of these technologies, LTE and WiMax, and to other evolved 3G technologies providing a substantial level of improvement in performance and capabilities with respect to the initial third generation systems now deployed. The detailed specifications of the IMT-Advanced technologies will be provided in a new ITU-R Recommendation expected in early 2012.
Read between the lines and you'll see that all the current technologies do not meet the 4G standard, but due to all the carriers misuse of the term, the ITU was basically forced to acknowledge existing enhanced networks as undefined "4G". Hooray for marketing!
It would be like car maufacturers making a more powerful 6 cylinder engine and calling it the "new 8 cylinder", or maybe "8C"