1. Multi Targetting.

2. Rich Web Designer and CSS Support, Split view mode.

3. CSS style Manager.

4. Fullly Nested Master Page support.

5. Javascript Intelisence.

6. Java script Debugging.

7. Creating Re-Usable ASP.NET AJAX Behaviors, Controls and Libraries.

8. Automatic Properties.

9. Extension Methods.

10. Lambda Expressions.

11. Linq to Sql (liq to sql,linq to dataset,linq to xml,linq to entities,linq to objects etc).

12. Nested Master Pages.

13. Anonymous Types.

14. Datapager Control.

15. Listview Control.