I wrote on the blog earlier this summer about a suit filed by HVAC indsutry associations challenging Albuquerque's green building code claiming that the energy requirements for the HVAC equipment was preempted (i.e. already regulated) by Federal law. http://greenlaw.blogspot.com/2008/07/green-building-litigation-hits-in-new.html
Yesterday, "Following months of debate and squabbling, the House of Representatives just passed a bill that could open America's coasts to offshore drilling, as well as extend the tax credits for clean energy and offer other incentives for clean power and green transportation." http://earth2tech.com/2008/09/16/house-approves-offshore-drilling-extends-clean-energy-credits/ One of the complaints Earth2Tech noted that the Republicans have voiced about the bill is that "the bill also creates a federal renewable portfolio standard that would require 15 percent of the nation's electricity to be generated from renewable sources. Going beyond states' mandates is viewed as a form of "big government" with which Republicans disagree."
In short, the Republicans are saying that the Federal government shouldn't pass sustainability regulations, and certain interest groups are suing to prevent states (and through them, municipalities) from regulating, it could create a quagmire in which no government entity is able to effectively pass sustainability regulations.