Are MicrosoftAjax.js, MicrosoftMvcAjax.js and MicrosoftMvcValidation.js obsolete as of ASP.NET MVC 3? I haven\'t been able to find muc         
        
You only need the MicrosoftAjax functionality if you are using the libraries. Microsoft AJAX does offer some functionality not found in the provided JQuery libraries (although could be replicated with plug-ins). If you are not using Microsoft AJAX within your application you can delete all reference to these scripts.