Microsoft has released the long awaited Service Pack 1 for .NET framework 3.5 and another for Visual Studio 2008. Both of these service packs are substantial product extensions, rather than just bug fixes. Their most dramatic effect is to reduce the size of libraries in the framework for client applications by 80 per cent.
The new, leaner version of the framework excludes all server-side classes, which reduces the size of the libraries from 197MB to 26.5MB. Developers can program in Visual Studio with this client profile – the IDE issues a warning when code classes not contained in the smaller framework are called.
An additional object-relational mapper has been added, called the ADO.NET Entity Framework. The ASP.NET Dynamic Data Controls support database-driven websites. These supplement LINQ to SQL, which was introduced in version 3.5 of the framework.
source : heise-online.co.uk