Disponbile la versione 3.5 di Microsoft .NET Framework, che include in sé anche .NET Framework 2.0 SP1 e .NET Framework 3.0 SP1.

Tra le novità:

• Deep integration of Language Integrated Query (LINQ) and data awareness. This new feature will let you write code written in LINQ-enabled languages to filter, enumerate, and create projections of several types of SQL data, collections, XML, and DataSets by using the same syntax.
• ASP.NET AJAX lets you create more efficient, more interactive, and highly-personalized Web experiences that work across all the most popular browsers.
• New Web protocol support for building WCF services including AJAX, JSON, REST, POX, RSS, ATOM, and several new WS-* standards.
• Full tooling support in Visual Studio 2008 for WF, WCF, and WPF, including the new workflow-enabled services technology.
• New classes in .NET Framework 3.5 base class library (BCL) that address many common customer requests.