The past few days have been terrific from a .NET developer standpoint. To make devs have more fun, Microsoft just shipped the final release of Visual Studio 2008 and .NET Framework 3.5 Service Pack 1which is much more than a simple update. There are some new features in areas such as WPF, data abstraction, ....
Another thing that's worth mentioning is the availability of .NET Client Framework which is a stripped down version of the full .NET Framework (just like J2SE/J2EE). It helps deployment of client applications by reducing the framework's footprint.
You can download the service pack here.