When this thread first started I dismissed it as political grandstanding for their constituents. It seems however as if they are serious and are going to actually try to do this. Does SF (or any other large city) have a mechanism for collecting that much debt so that they could come up with the 250 Billion the article Fly320s linked mentions? If they assume the Feds are going to bail them out on this bill they are smoking crack, at least during this congress, and I suspect that this would be a pretty serious sticking point for a large chunk of the country.
I mean if SF voters want to do this with their money, It's dumb, and will probably destroy their city, but it's their money. They better not want other peoples money though.