Changes to height zoning laws?

Seattle Times, Seattle buildings going tall for the middle class:

Mayor Greg Nickels is considering a proposal to raise height limits on residential buildings in the Interbay, South Lake Union and South Downtown neighborhoods — on the condition that developers create some units for people who make too much money to qualify for government-subsidized housing, but not enough to buy one of the pricey condominiums going up downtown.

The Tim at Seattle Bubble had this to say about the article:

I still think the government is pretty powerless to make significant changes to the housing affordability landscape. However, at least this plan is attacking the problem by increasing supply (by leaning on the builders), as opposed to most programs that simply increase demand (by pouring money into grant programs).