Verizon's will, assuming they don't cap LTE, in a few years, assuming Clear doesn't upgrade their equipment. AT&T will probably be another couple years after that in terms of rolling out LTE, so Clear has time...
Umm No Clearwire is for not choosing a global standard for true 4G. And AT&T and Verizon LTE hasn't even been launched yet. But because it's using the 700mhz frequency it will easily dominate Wi-Max -- I get 29 MPG in my Toyota Highlander Hybrid!