Earlier this month, Google introduced "Video Sitemaps" as an extension to the Sitemap Protocol standard. It allows website owners to expose their video content (including embedded video) to be indexed and included in Google's video search (here is Google's spec). Embrace and extend ;)

I just added this to Dallas Theological Seminary's site: http://www.dts.edu/videositemap.xml and I thought it might help to share the template to speed someone else's development:

using System;
using System.Data;
using System.Configuration;
using System.Collections.Generic;
using System.Web;
using System.Xml;
using System.Text;

namespace YourNamespace
{
    public class VideoSiteMap : IHttpHandler
    {
        public VideoSiteMap()
        {
        } 
        
        public void ProcessRequest(HttpContext context)
        {
            XmlTextWriter writer = new XmlTextWriter(context.Response.OutputStream, Encoding.UTF8); 
            context.Response.ContentType = "text/xml";

            writer.Formatting = Formatting.Indented;
            writer.WriteStartDocument(); 
            writer.WriteStartElement("urlset");
            
            // add namespaces
            writer.WriteAttributeString("xmlns", "http://www.sitemaps.org/schemas/sitemap/0.9");
            writer.WriteAttributeString("xmlns", "video", null, "http://www.google.com/schemas/sitemap-video/1.0");
            
            // fake loop
            for (int i=0; i<10; i++) {
                writer.WriteStartElement("url");

				// required
                writer.WriteElementString("loc", "http://mysite.com/myplayer.aspx");
                writer.WriteStartElement("video", "video", null); 
                
                // start:optional
                writer.WriteElementString("video", "title", null, "Video Title");
                writer.WriteElementString("video", "description", null, "a great video");
                writer.WriteElementString("video", "thumbnail_loc", null, "http://mysite.com/myvideothumb.jpg");
                writer.WriteElementString("video", "family_friendly", null, "Yes");
                writer.WriteElementString("video", "content_loc", null, "http://mysite.com/myvideo.flv");
                writer.WriteElementString("video", "duration", null, "100");                    
                
                writer.WriteStartElement("video", "player_loc", null);                
                writer.WriteAttributeString("allow_embed", "true");
                writer.WriteString("http://mysite.com/embeddedplayer.swf");
                writer.WriteEndElement(); // video:player_loc
                // end:optional
                
                writer.WriteEndElement(); // video:video
                writer.WriteEndElement(); //url
            }
            
            writer.WriteEndElement(); //urlset 
            writer.WriteEndDocument();
            writer.Close();
        }
        public bool IsReusable
        {
            get { return false; }
        }
    }
}

Just add this class to your web.config and you're all set:

<system.web>
   <httpHandlers>
      <add verb="*" path="videositemap.xml" type="YourNamespace.VideoSiteMap, YourNamespace"/>
   </httpHandlers>
</system.web>

Hope that helps!