I'm sure most of you have heard already - but thought I'd add it here for completeness.  We've just released VS2008 SP1 and along with it the .NET Framework v3.5 SP1.  Some of my personal favorite highlights are:

• Performance increases between 20-45% for WPF-based applications - without having to change any code
• Improvements in the area of data platform, such as the ADO.NET Entity Framework, ADO.NET Data Services  and extensive support for SQL Server 2008’s new features
• How big was the .NET Framework 3.5 full redistributable package?
  197 MB
• How big was the .NET Framework 3.5 bootstrapper?
  2.7 MB
• How big is the .NET Framework Client Profile full redistributable package?
  26.5MB.  That is an 86.5% reduction in the size of the package.
• How big is the .NET Framework Client Profile bootstrapper?
  Approximately 0.5MB.  That is approximately 20% of the size of the .NET Framework 3.5 bootstrapper.

Pretty, cool, eh?  Check it out.