Have both been released this month! Visual Studio 2008 Service Pack 1 (As a beta) can be found here: http://msdn.microsoft.com/en-us/vstudio/products/cc533447.aspx It includes some enhancements, however most noticeably the improvements in event wiring up in WPF, between the design view and the code behind.
Enterprise Library 4 can be found here: http://msdn.microsoft.com/en-us/library/cc512464.aspx It is for .NET 3.5 and Visual Studio 2008, so fits well with the release of SP1. The enhancements can be found here: http://www.codeplex.com/entlib/Wiki/View.aspx?title=EntLib4%20Backlog.
