When I installed MVC4 beta on a development PC, it had a template for SPA (Single Page Application). Today on a different PC with the same setup (VS2010 SP1, win7), I installed
You can get the SPA template in the Fall 2012 update. More information on the template here and here.
Changes from ASP.NET MVC 4 Beta
The major changes from ASP.NET MVC 4 Beta in this release are summarized below:
Removed ASP.NET Single Page Application: ASP.NET Single Page Application (SPA) shipped with ASP.NET MVC 4 Beta as an early preview of the experience for building applications that include significant client-side interactions using JavaScript. SPA won’t ship with the final MVC 4 release, but will continue to evolve outside of the MVC 4 release. Check out the ASP.NET SPA home page for details.
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http://www.asp.net/whitepapers/mvc4-release-notes
P.S., Wow I am glad that I didn't use it for an app I build right now. I was considering it 3 months ago, but decided not to risk it because MS said that it is experimental.
It`s very risky now
For example if you try to run it with System.json for serialization it runs well with WebApi and DBDATAContext methods but it`s impossible to use it with Entities relationship entity circular errors and so on. (There is a solution to change private access of method get, but would be too much work to have to change in all the access methos of all your entities.