The Enterprise Library 4.0 (May 2008) final release is now available to download. These are some of the new features in this version:

Visual Studio 2008 support
Integration with Unity
Windows Management Instrumentation (WMI) 2.0 support and improved instrumentation
Pluggable Cache Managers
Performance improvements
Bug fixes
…and more

You can find more details about this release in Grigori's blog.
In addition, we have just [...]