LINQ essentially is the composition of many standard query operators that allow you to work with data in a more intuitive way regardless.
The benefits of using LINQ are significant – Compile time checking C# language queries, and the ability to debug step by step through queries.
Visual Studio LINQ Designer
Already you know in VS 2005 we have inbuilt SQL Server IDE feature. by this you no need to use any other tools like SQL Server Query Analyzer and SQL Server Enterprise Manger. You have directly database explorer by this you can create connections to your database and you can view the tables and stored procedures in VS IDE itself. But now in VS 2008 it has View Designer window capability with LINQ-to-SQL.
Expression Blend Support
Windows Presentation Foundation
WPF provides you an extensive graphic functionality you never seen these before. Visual Studio 2008 contains plenty of WPF Windows Presentation Foundation Library templates. By this a visual developer who is new to .NET, C# and VB.NET can easily develop the 2D and 3D graphic applications.
Visual Studio 2008 provides free game development library kits for games developers. currently this game development kits are available for C++ and also 2D/3D Dark Matter one image and sounds sets.
VS 2008 Multi-Targeting Support
Earlier you were not able to working with .NET 1.1 applications directly in visual studio 2005. Now in Visual studio 2008 you are able to create, run, debug the .NET 2.0, .NET 3.0 and .NET 3.5 applications. You can also deploy .NET 2.0 applications in the machines which contains only .NET 2.0 not .NET 3.x.
AJAX support for ASP.NET
Previously developer has to install AJAX control library separately that does not come from VS, but now if you install Visual Studio 2008, you can built-in AJAX control library. This Ajax Library contains plenty of rich AJAX controls like Menu, TreeView, webparts and also these components support JSON and VS 2008 contains in built ASP.NET AJAX Control Extenders.
Nested Master Page Support
Already Visual Studio 2005 supports nested master pages concept with .NET 2.0, but the problem with this Visual Studio 2005 that pages based on nested masters can't be edited using WYSIWYG web designer. But now in VS 2008 you can even edit the nested master pages.
Intellisense Support: When we are writing the LINQ Query VS provides LINQ query syntax as tool tips.
Organize Imports or Usings: We have Organize Imports feature already in Eclipse. SInce many days I have been waiting for this feature even in VS. Now VS contains Organize Imports feature which removes unnecessary namespaces which you have imported. You can select all the namespaces and right click on it, then you can get context menu with Organize imports options like "Remove Unused Usings", "Sort Usings", "Remove and Sort". Refactoring support for new .NET 3.x features like Anonymous types, Extension Methods, Lambda Expressions.
Intellisense Filtering: Earlier in VS 2005 when we were typing with intellisense box all the items were being displayed. For example If we type the letter 'K' then intellisense takes you to the items starts with 'K' but also all other items will be presented in intellisense box. Now in VS 2008 if you press 'K' only the items starts with 'K' will be filtered and displayed.
Intellisense Box display position
Earlier in some cases when you were typing the an object name and pressing . (period) then intellisense was being displayed in the position of the object which you have typed. Here the code which we type will go back to the dropdown, in this case sometimes programmer may disturb to what he was typing. Now in VS 2008 If you hold the Ctrl key while the intellisense is dropping down then intellisense box will become semi-transparent mode.
Visual Studio 2008 Split View
VS 205 has a feature show both design and source code in single window. but both the windows tiles horizontally. In VS 2008 we can configure this split view feature to vertically, this allows developers to use maximum screen on laptops and wide-screen monitors.
Here one of the good feature is if you select any HTML or ASP markup text in source window automatically corresponding item will be selected in design window.
Debugging .NET Framework Library Source Code:
Now in VS 2008 you can debug the source code of .NET Framework Library methods. Lets say If you want to debug the DataBind() method of DataGrid control you can place a debugging point over there and continue with debug the source code of DataBind() method.
In built Silverlight Library
Earlier we used to install silverlight SDK separately, Now in VS 2008 it is inbuilt, with this you can create, debug and deploy the silverlight applications.
Inbuilt C++ SDK
Earlier It was so difficult to download and configure the C++ SDK Libraries and tools for developing windows based applications. Now it is inbuilt with VS 2008 and configurable
Multilingual User Interface Architecture - MUI
MUI is an architecture contains packages from Microsoft Windows and Microsoft Office libraries. This supports the user to change the text language display as he wish.
Visual Studio is now in English, Spanish, French, German, Italian, Chinese Simplified, Chinese Traditional, Japanese, and Korean. Over the next couple of months. Microsoft is reengineering the MUI which supports nine local languages then you can even view Visual studio in other 9 local languages.
Microsoft Popfly Support
Microsoft Popfly explorer is an add-on to VS 2008, by this directly you can deploy or hosting the Silverlight applications and Marshup objects