Err, well actually, my understanding (probably wrong) was that as of the end of 2009 there were two candidate technologies that had been submitted to ITU-R (http://en.wikipedia.org/wiki/ITU-R). These technologies are LTE Advanced (http://en.wikipedia.org/wiki/LTE_Advanced) and 802.16m (http://en.wikipedia.org/wiki/802.16m) more commonly known as WiMAX. There currently seems to be more support for LTE and it's successor LTE Advanced, but at this point, both can be validly be called 4G.