North Texas is really setting the standard for Sunbelt population cities. Fort Worth seems like it's finally getting on the train, activating the pre-air conditioning downtown setting; Dallas has certainly realized a return to the ways of higher population density, and that downtown has a solid foundation, is building an environment for greater and greater population within a fixed area.
Plano, on the other hand, is breaking new ground. No coincidence that there's an apparent culture struggle as the armada of low density single family home neighborhoods that put Plano on the Corporate America map with EDS, JCPenny, Dr Pepper, Fritos, etc is disgruntled that the next phase of corporate campus building requires thorough and hefty infusion of urban into the suburb landscape.
Plano needs another 200,000 people living in townhomes, apartments and mid & highrise dwellings. The trick is finding a place to put all these people. It's Great.