Regardless of the cost and what the providers think, I'm all for getting a Broadband Map of the US done. For one it'll really give us an idea of what our infrastructure is like and where it needs work. For another (and this is one reason the ISPs are so against it generally), it'll point out just how "broad" broadband is, and where the speeds can hardly be considered better than dial-up.
I think that the government should issue an ultimatum to ISPs and demand that relevant information is handed over in proper format and detail, and a timely manner. Then the government can contract out the actual mapping of various states or regions to companies from there. Based on what the article at GigaOM said, with 5-6 months per state, if enough mapping companies get in on this, we can have a nationwide map in a two years or so, maybe less depending on the circumstances.