From the USGS National Geospatial Program (NGP):
During this year, National Atlas of the United States and The National Map will transition into a combined single source for geospatial and cartographic information. This transformation is projected to streamline access to maps, data and information from the USGS National Geospatial Program (NGP). This action will prioritize our civilian mapping role and consolidate core investments while maintaining top-quality customer service.
The USGS will continue its long history of providing topographic maps, geospatial data and other geographic information by offering a range of scales and layers of geospatial information on The National Map Viewer and through US Topo maps. As a result of the conversion to an integrated single source for geospatial and cartographic information, nationalatlas.gov will be removed from service on September 30, 2014.
“We recognize how important it is for citizens to have access to the cartographic and geographic information of our nation. We are committed to providing that access through nationalmap.gov”, said Mark DeMulder, NGP Director.
“We value the National Atlas customers and stakeholders and want to make this transition as easy as possible,” explained Jay Donnelly, the National Atlas Program Manager.” We will post updates to The National Map and National Atlas Websites as this transition unfolds, including information on the future availability of the products and services currently delivered by nationalatlas.gov.”
Further information is available at: http://nationalatlas.gov/transitionfaq.html.
… Perhaps downloading data now might not be a bad idea if you need it!