Started implementing new IPublishedMediaStore which will replace the notion of the legacy ExamineBackedMedia and

moving forward will open up many nice opportunities. This will be used for the media accessor in the new DynamicDocument.
Renamed XmlPublishedContentStore to just DefaultPublishedContentStore.
Made GetProperty an extension method for IDocument and removed from the interface as it is not needed there.

src/Umbraco.Web/DefaultPublishedContentStore.cs

@@ -0,0 +1,144 @@
+using System;
+using System.Text;
+using System.Xml;
+using System.Xml.Linq;
+using Umbraco.Core.Models;
+using Umbraco.Web.Routing;
+using umbraco;
+using umbraco.NodeFactory;
+using umbraco.interfaces;
+
+namespace Umbraco.Web
+{
+	/// <summary>
+    /// An IPublishedContentStore which uses the Xml cache system to return data
+    /// </summary>
+    internal class DefaultPublishedContentStore : DefaultPublishedMediaStore, IPublishedContentStore
+    {
+
+    	private IDocument ConvertToDocument(XmlNode xmlNode)
+		{
+			if (xmlNode == null)
+				return null;
+
+			return new Models.XmlDocument(xmlNode);
+		}
+		
+    	public override IDocument GetDocumentById(UmbracoContext umbracoContext, int nodeId)
+    	{
+    		if (umbracoContext == null) throw new ArgumentNullException("umbracoContext");
+
+    		return ConvertToDocument(GetXml(umbracoContext).GetElementById(nodeId.ToString()));
+    	}
+
+		public IDocument GetDocumentByRoute(UmbracoContext umbracoContext, string route, bool? hideTopLevelNode = null)
+        {
+			if (umbracoContext == null) throw new ArgumentNullException("umbracoContext");
+			if (route == null) throw new ArgumentNullException("route");
+
+			//set the default to be what is in the settings
+			if (hideTopLevelNode == null)
+			{
+				hideTopLevelNode = GlobalSettings.HideTopLevelNodeFromPath;
+			}
+
+			//the route always needs to be lower case because we only store the urlName attribute in lower case
+        	route = route.ToLowerInvariant();
+
+            string startNodeIdString = "0";
+            string path = route;
+            if (!route.StartsWith("/"))
+            {
+                int pos = route.IndexOf('/');
+                startNodeIdString = route.Substring(0, pos);
+                path = route.Substring(pos + 1);
+            }
+            int startNodeId = int.Parse(startNodeIdString);
+
+            var xpath = CreateXpathQuery(startNodeId, path, hideTopLevelNode.Value);
+
+        	return ConvertToDocument(GetXml(umbracoContext).SelectSingleNode(xpath));
+        }
+
+		public IDocument GetDocumentByUrlAlias(UmbracoContext umbracoContext, int rootNodeId, string alias)
+        {
+			if (umbracoContext == null) throw new ArgumentNullException("umbracoContext");
+			if (alias == null) throw new ArgumentNullException("alias");
+
+			// the alias may be "foo/bar" or "/foo/bar"
+            // there may be spaces as in "/foo/bar,  /foo/nil"
+            // these should probably be taken care of earlier on
+
+            alias = alias.TrimStart('/');
+            var xpathBuilder = new StringBuilder();
+            xpathBuilder.Append("/root");
+            if (rootNodeId > 0)
+                xpathBuilder.AppendFormat("//*[@isDoc and @id={0}]", rootNodeId);
+            xpathBuilder.Append("//*[@isDoc and (");
+            xpathBuilder.AppendFormat("contains(concat(',',translate(umbracoUrlAlias, ' ', ''),','),',{0},')", alias);
+            xpathBuilder.AppendFormat(" or contains(concat(',',translate(umbracoUrlAlias, ' ', ''),','),',/{0},')", alias);
+            xpathBuilder.Append(")]");
+
+            var xpath = xpathBuilder.ToString();
+
+			return ConvertToDocument(GetXml(umbracoContext).SelectSingleNode(xpath));
+        }
+
+		XmlDocument GetXml(UmbracoContext umbracoContext)
+		{
+			if (umbracoContext == null) throw new ArgumentNullException("umbracoContext");
+
+			return umbracoContext.GetXml();
+		}
+
+		static readonly char[] SlashChar = new char[] { '/' };
+
+        protected string CreateXpathQuery(int startNodeId, string path, bool hideTopLevelNodeFromPath)
+        {
+            string xpath;
+
+            if (path == string.Empty || path == "/")
+            {
+                // if url is empty
+                if (startNodeId > 0)
+                {
+                    // if in a domain then use the root node of the domain
+                    xpath = string.Format("/root//*[@isDoc and @id={0}]", startNodeId);
+                }
+                else
+                {
+                    // if not in a domain - what is the default page?
+                    // let's say it is the first one in the tree, if any
+                    xpath = "(/root/*[@isDoc])[1]";
+                }
+            }
+            else
+            {
+                // if url is not empty, then use it to try lookup a matching page
+                var urlParts = path.Split(SlashChar, StringSplitOptions.RemoveEmptyEntries);
+                var xpathBuilder = new StringBuilder();
+                int partsIndex = 0;
+
+                xpathBuilder.Append("/root");
+				
+                if (startNodeId == 0)
+                {
+                    if (hideTopLevelNodeFromPath)
+                        xpathBuilder.Append("/*[@isDoc]"); // first node is not in the url
+                }
+                else
+                {
+                    xpathBuilder.AppendFormat("//*[@isDoc and @id={0}]", startNodeId);
+                    if (!hideTopLevelNodeFromPath)
+                        xpathBuilder.AppendFormat("[@urlName='{0}']", urlParts[partsIndex++]); // first node is in the url
+                }
+                while (partsIndex < urlParts.Length)
+                    xpathBuilder.AppendFormat("/*[@isDoc and @urlName='{0}']", urlParts[partsIndex++]);
+
+                xpath = xpathBuilder.ToString();
+            }
+
+            return xpath;
+        }
+    }
+}