MSDN just published some
pages
describing each Application Blocks distributed in the Enterprise
Library
. And there is a good news written in the Roadmap:

“An updated release of the Security Application Block is planned for the next
release of Enterprise Library. This release will target the .NET Framework 2.0
and Visual Studio 2005.

The Security Application Block will be updated to work with the .NET
Framework 2.0 and may include additional improvements based on customer
feedback.”