State GIS clearinghouses have posted over 19,000 data layers online with thousands more in progress. The National States Geographic Information Council just completed their mid-year meeting and circulated updates on data efforts around the country.
The GIS Inventory website offers maps and lists of the data layers available [right, example of states serving soil maps under the Geo-Scientific category. Credit GISInventory.net]
Data Layers Documented: 19091
Users Documenting Data: 1264
Total Registered Users: 3753
Complete Layers: 16103
In work Layers: 2531
Planned Layers: 457