mpls: "room to run"

Sometimes its nice to get some perspective. There's a few week old article in the New York Times magazine about corporately-owned development. The amount of money that's at stake is mindboggling:

You can see how it adds up in the end: the stealthy land acquisition, the aggressive legal positioning, the mandering street designs, the furiously gabled architecture, the fungible options and home facades, the demograhic targets -- an entire vertically integrated, highly methodological luxury system. Not long ago, Fortune magazine estimated that the company would make around $100 million on the Estates at Princeton Junction.

The article quotes some wonk named Robert Lang:

The Los Angeles metro area is not far behind [in becoming fully developed, or "built out."] Again, the distinction between these areas and Minneapolis or Phoenix -- "places that still have a lot of room to run," according to Lang -- is that not every field of wildflowers will be paved into parking lots or built into bungalows for empty nesters.

What does this even mean? When is Wirth Park going to be paved, again?