Best place to set CurrentCulture for multilingual ASP.NET MVC web applications

For multilingual ASP.NET MVC 3 web application, I am determining the Thread.CurrentThread.CurrentCulture and Thread.CurrentThread.CurrentUICulture on the controller factory as follows:

public class MyControllerFactory : DefaultControllerFactory {

    protected override IController GetControllerInstance(System.Web.Routing.RequestContext requestContext, Type controllerType) {

        //Get the {language} parameter in the RouteData
        string UILanguage;
        if (requestContext.RouteData.Values["language"] == null)
            UILanguage = "tr";
        else
            UILanguage = requestContext.RouteData.Values["language"].ToString();

        //Get the culture info of the language code
        CultureInfo culture = CultureInfo.CreateSpecificCulture(UILanguage);
        Thread.CurrentThread.CurrentCulture = culture;
        Thread.CurrentThread.CurrentUICulture = culture;

        return base.GetControllerInstance(requestContext, controllerType);
    }

}

The above code is nearly a year old now! So, I open for suggestions.

And I register this on the Global.asax file like:

ControllerBuilder.Current.SetControllerFactory(new MyControllerFactory());

This is working good but I am not sure if it is the best practice and best place to do this type of action.

I haven't dug into the main role of ControllerFactory and I am unable to compare it against ActionFilterAttribute.

What do you think about the best place to do this type of action?