This first ASP.NET 3.5 Extensions preview release includes:

• ASP.NET AJAX Improvements: New ASP.NET AJAX features in the ASP.NET 3.5 Extensions release include better browser history support (back/forward button integration, and server-side history management support), improved AJAX content linking support with permalinks, and additional JavaScript library improvements.

• ASP.NET MVC: This model view controller (MVC) framework for ASP.NET provides a structured model that enables a clear separation of concerns within web applications, and makes it easier to unit test your code and support a TDD workflow. It also helps provide more control over the URLs you publish in your applications, and more control over the HTML that is emitted from them.

• ASP.NET Dynamic Data Support: The ASP.NET 3.5 Extensions release delivers new features that enable faster creation of data driven web sites.  It provides a rich scaffolding framework, and will enable rapid data driven site development using both ASP.NET WebForms and ASP.NET MVC.

• ASP.NET Silverlight Support: With the ASP.NET 3.5 Extensions release we'll deliver support for easily integrating Silverlight within your ASP.NET applications.  Included will be new controls that make it easy to integrate Silverlight video/media and interactive content within your sites.

• ADO.NET Data Services: In parallel with the ASP.NET Extensions release we will also be releasing the ADO.NET Entity Framework.  This provides a modeling framework that enables developers to define a conceptual model of a database schema that closely aligns to a real world view of the information.  We will also be shipping a new set of data services (codename "Astoria") that make it easy to expose REST based API endpoints from within your ASP.NET applications.