National Public Radio: Plastic bags may have become victims of their own success. Their very ubiquity — an estimated 90 billion plastic bags are used in the United States each year — has led to a small but growing number of jurisdictions discouraging their use through fees or outright bans. Last week, the California Assembly voted to approve the first statewide ban on both plastic and paper “single-use” bags. Republican Gov. Arnold Schwarzenegger has said he’ll sign the bill if it makes it to his desk. …