I tried tutorial put report in MVC http://www.youtube.com/watch?v=t-iA05KpDFM

I have this error for my report

c:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files\root\40275438\83dd9ced\App_Web_testreport.aspx.34631e4.fdgmfmtb.0.cs(247): error CS0234: The type or namespace name 'Reporting' does not exist in the namespace 'Telerik' (are you missing an assembly reference?)

I already have telerik.reporting and telerik.reportviewer.webforms in my reference folder.

Anyone has any idea what goes wrong?

This is general .net exception and it looks that there is something wrong with the references in your project.
I downloaded an MVC project with telerik reporting from here(the project from the video). Updated the references. Also I changed all wrong dll versions and it works.
E.g.
<add path="Telerik.ReportViewer.axd" verb="*" type="Telerik.ReportViewer.WebForms.HttpHandler, Telerik.ReportViewer.WebForms, Version=4.2.12.1017, Culture=neutral, PublicKeyToken=a9d7983dfcc261be"