• SQL Server 2008 Service Pack 1 Released:
  • Information: http://blogs.technet.com/dataplatforminsider/archive/2009/04/07/service-pack-1-for-sql-server-2008-available-today.aspx
  • Download: http://www.microsoft.com/downloads/details.aspx?FamilyID=6f26fc45-f0ca-49cf-a6ee-840c7e8bb8af&displaylang=en
• Internet Explorer 8 Released:
  • Information: http://www.microsoft.com/windows/internet-explorer/default.aspx
  • Download: http://www.microsoft.com/windows/internet-explorer/worldwide-sites.aspx
• ASP.NET MVC 1.0 Released:
  • Information: http://www.asp.net/mvc/
  • Download: http://www.microsoft.com/downloads/details.aspx?FamilyID=53289097-73ce-43bf-b6a6-35e00103cb4b&displaylang=en
• Expression Blend 3 Preview Released:
  • Information: http://www.microsoft.com/expression/try-it/blendpreview.aspx
  • Download: http://www.microsoft.com/downloads/details.aspx?FamilyID=a04aa0ae-87be-4201-a65e-e792859122fc&displaylang=en
• Silverlight 3 Beta Released:
  • Information: http://silverlight.net/themes/silverlight/getstarted/sl3beta.aspx
  • Download: http://www.microsoft.com/downloads/details.aspx?FamilyId=11dc7151-dbd6-4e39-878f-5081863cbb5d&displaylang=en
• Microsoft Web Platform Installer 1.0 and 2.0 Beta Released:
  • Information: http://www.microsoft.com/web/downloads/platform.aspx
  • Download:
    • 1.0: http://go.microsoft.com/?linkid=9588072
    • 2.0 Beta: http://go.microsoft.com/fwlink/?LinkID=145505

Taken from the update page:

An update for the Microsoft .NET Framework 3.5 Service Pack 1 (SP1) is available. This article describes information about the issues that the update for the .NET Framework 3.5 SP1 fixes.

The update for the .NET Framework 3.5 SP1 fixes the issues that are described in the following articles in the Microsoft Knowledge Base:

• 958481  List of the breaking issues with the .NET Framework 2.0 Service Pack 2 after you upgrade to the .NET Framework 3.5 Service Pack 1
• 958483  List of the breaking issues with the .NET Framework 3.0 Service Pack 2 after you upgrade to the .NET Framework 3.5 Service Pack 1
• 958484  List of the breaking issues with the .NET Framework 3.0 Service Pack 1 after you upgrade to the .NET Framework 3.5 Service Pack 1

Joe Healy has blogged about this update and mentions some of the important fixes:

Interesting items fixed (note a full list can be found via the KB) – dynamic data one to one relationships – ASP.NET BrowsCap being broken of FPSE are installed – some broken UpdateProgress control issues – changes in the AutoCommit behavior for Oracle transactions – problems with WPF generating images on the fly via ASP.NET on IIS – and some other fairly freaky stuff – read the kb for all details.

I installed this update today on my Vista x64 work machine and it is actually 3 seperate updates which have to be downloaded and installed in a specific order. Please be sure to read the KB documention as to the order in which to install the updates.