What is new in ASP.Net MVC 5

Summary : ASP.Net MVC 5 is a part of Dot.Net framework 4.5 that is releases with VS2013.  Key new feature includes

1. One ASP.Net, 
2. ASP.Net Identity for External Authentication like google, 
3. Enhance Async Controller, 
4. WEB API Ver 2,0, 
5. Support of EF 6, 
6. Attribute based routing, Bootstrap, 
7. OWIN and Katana for cloud enhance cloud support.

Here is the very brief summary of key new features of MVC 5.

1. One ASP.Net : Is is actually an improvement over previous project model that allow to use MVC feature in ASP project and ASP features in MVC project without any special tweaks. 
2. External Authentication (ASP.Net Identity) : This feature provides out if the box support for OAUTH based authentication provides like Google.
3. Authentication filters : Theses are new integration points to implement custom authentication as well as third party authentication. This saves a lot of effort when it comes to 
4. Attribute based Filter overrides : This feature allows to override default authentication settings just by applying an attribute on an action or controller.
5. Enhance Async Controller: Async controller has been enhance and only return task async result
6. Web API 2.0 : This version of Web API provides additional support for Odata like $expand and $select.
7. Bootstrap : It is a css library that provide native support for adaptive rendering.
8. Attribute based routing: This facilitate HTTP routing just by applying an routing attribute on any action method. Default route map is still available.  
9. OWIN and Katana : Katana is an implementation of OWIN standard that is mainly optimized for developing lightweight web APIs and application on cloud.
10. SignalR: A new library to provide unified communication model for all web socket based communication. http://signalr.net/
11. Entity Framework 6: This version of MVC has support of EF 6.0 that has some advance features like AsyncQueries.

References

1. http://exsertus.wordpress.com/2013/10/18/asp-net-mvc-5-whats-new/ 
2. http://channel9.msdn.com/Events/Visual-Studio/Launch-2013/WC106
3. http://www.dotnetcurry.com/showarticle.aspx?ID=941
4. http://channel9.msdn.com/Shows/Web+Camps+TV/The-Katana-Project-OWIN-for-ASPNET
5. http://www.asp.net/aspnet/overview/owin-and-katana/an-overview-of-project-katana