The Web Application Development Frameworks (Web ADFs) provide a developer kit for the JSF and ASP.NET developer.
While ESRI will continue supporting existing JSF and ASP.NET developers with quality improvements and technology updates to the Web ADFs, major emphasis will be put on the ArcGIS Web Mapping APIs. For example, the ArcGIS Web Mapping APIs will incorporate support for all new services and enhanced service capabilities included with ArcGIS Server 10 (e.g., Feature Service, Time support, etc.). The Web ADFs will not incorporate these new features.
Based on customer feedback and technology trends, we see the Web ADFs playing a decreasing role amongst ArcGIS Server developers in favor of alternatives such as the ArcGIS Web Mapping APIs.
The Web ADFs will be deprecated in the next release after ArcGIS Server 10.