Where is Html.Image in ASP .NET MVC RC

public static class HtmlHelperExtensions
{

    public static string Image( this HtmlHelper helper,
                                string url,
                                string altText,
                                object htmlAttributes )
    {
        TagBuilder builder = new TagBuilder( "img" );
        builder.Attributes.Add( "src", url );
        builder.Attributes.Add( "alt", altText );
        builder.MergeAttributes( new RouteValueDictionary( htmlAttributes ) );
        return builder.ToString( TagRenderMode.SelfClosing );
    }
}

<%= Html.Image( Url.Content( "~/Content/images/img.png" ),
               "alt text",
               new { id = "myImage", border = "0" } )
 %>

<img src="<%= Url.Content( "~/content/..." ) %>"
     alt="alt text"
     class="has-border" />

<img src="" alt="" />

<img src="<%= ViewData["ImageSource"] %>" alt="" />

<img src="<%= ViewData.Model.ImageSource %>" alt="" />

<img src="<%= ResolveUrl(ViewData.Model.ImageSource) %>" alt="" />

public static MvcHtmlString Image(this HtmlHelper helper, string url, string altText, object htmlAttributes)
        {
            TagBuilder builder = new TagBuilder("img");
            builder.Attributes.Add("src", url);
            builder.Attributes.Add("alt", altText);
            builder.MergeAttributes(new RouteValueDictionary(htmlAttributes));
            return MvcHtmlString.Create(builder.ToString(TagRenderMode.Normal));
        }

@Html.Image( Url.Content( "~/Content/images/img.png" ),
               "alt text",
               new { id = "myImage", border = "0" } )

<img src="/Content/image/mypic.png" alt="a picture available anywhere" />