The State of Tennessee's Office of Information Resources GIS Division (OIR-GIS) has released a draft technical specification document for its future-planned statewide "enhanced elevation" products. While the business plan for this program has yet to be funded, the State OIR-GIS seeks input / comments from its potential audience of users, especially local government authorities who have specific mapping needs (such as Knox). The draft document can be found here. For more information about this project, go to the State's GIS website.