InheritedClassModelBinder: A ModelBinder for ASP.NET MVC3 that handles creating concrete class instances mapped to an abstract superclass. Based on code by Kelly.

InheritedClassModelBinder.cs

namespace JoelPurra.Web.Binders
{
    using System;
    using System.Diagnostics.Contracts;
    using System.Linq;
    using System.Web.Mvc;
    using rDoing.Scraper.Web.Mvc.Controllers.ViewModels.Binder.Helpers;

    /// <remarks>
    ///     Based on
    ///         http://stackoverflow.com/questions/5460081/asp-net-mvc-3-defaultmodelbinder-with-inheritance-polymorphism
    ///         http://stackoverflow.com/questions/5460081/asp-net-mvc-3-defaultmodelbinder-with-inheritance-polymorphism/7517655#7517655
    ///         http://stackoverflow.com/questions/4012217/asp-net-mvc-2-binding-to-abstract-model
    ///         http://stackoverflow.com/questions/4012217/asp-net-mvc-2-binding-to-abstract-model/7517417#7517417
    ///         
    ///     Original by Kelly
    ///         http://stackoverflow.com/users/85802/kelly
    ///         
    ///     Edited by Joel Purra
    ///         https://gist.github.com/2415633
    /// </remarks>
    public class InheritedClassModelBinder : DefaultModelBinder
    {
        protected override object CreateModel(ControllerContext controllerContext, ModelBindingContext bindingContext, Type modelType)
        {
            if (modelType.IsAbstract)
            {
                // modelType is the abstract base class
                // concreteModelTypeName is the concrete subclass
                var concreteModelTypeName = ContextValueHelper.GetValue(controllerContext, bindingContext, "ModelTypeName");

                Contract.Assert(concreteModelTypeName != null, "View does not contain ModelTypeName");

                var type = modelType.Assembly.GetTypes().SingleOrDefault(x => x.IsSubclassOf(modelType) && x.Name == concreteModelTypeName);

                Contract.Assert(type != null, "Invalid ModelTypeName");

                var instance = bindingContext.Model ?? base.CreateModel(controllerContext, bindingContext, type);

                bindingContext.ModelMetadata = ModelMetadataProviders.Current.GetMetadataForType(() => instance, type);

                return instance;
            }

            return base.CreateModel(controllerContext, bindingContext, modelType);
        }
    }
}

Using a custom model binder to bind concrete subclasses to an abstract superclass. Found the question ASP.NET MVC 3: DefaultModelBinder with inheritance/polymorphism and used the answer from by Kelly, Kelly has added a new revision of the code in the answer to another question, ASP.NET MVC 2 - Binding To Abstract Model. I will post my version of the code here, as it's easier to keep track of it on gist.

In case you see the reference to SharpArch.Web.Mvc.ModelBinder in any of the revisions it's because I'm using SharpModelBinder as a base class in my local version.