Whither Phoenix?

David Leonhardt has a useful primer on who will benefit from Obama's housing plan:

[Negative equity homeowners] are precisely the sort who seem as if they have done nothing wrong. They seem like innocent victims of the housing crash. The new plan will help some of them refinance their mortgage at a lower rate. But only loans backed by Fannie Mae and Freddie Mac not many of the subprime loans at the heart of the foreclosure problem will be eligible. And the loan cannot exceed 105 percent of the current value of the property. Since prices have fallen almost 50 percent in some areas, like Phoenix, Las Vegas and parts of Florida, the cap will exclude many homeowners.