Status of 4G mobile networks

Here is a good summary of the status of 4G network deployment of various US mobile operators.

While Sprint is far ahead of others in terms of the deployment start (supposed to be this year vs. much later for other carriers), it is also going alone with WiMax. Most of the other carriers have decided to go with LTE (Long Term Evolution) technology. Sprint has a tough challenge ahead of itself with massive amount of debt from botched (paid too much for too little) acquisition of Nextel. Let's see how the WiMax deployment turns out.