I'm following the documentation here http://msdn.microsoft.com/en-us/library/windows/apps/hh465429.aspx, and I have managed to create a live tile for my app.
However the documentation does not say how to populate the live tile with content, and I'm not sure how to do this. My code is here
Windows.UI.Notifications.TileUpdateManager.createTileUpdaterForApplication().enableNotificationQueue(true);
var template = Windows.UI.Notifications.TileTemplateType.tileWide310x150Text04;
var tileXml = Windows.UI.Notifications.TileUpdateManager.getTemplateContent(template);
// TO DO: Fill in the template with your tile content. Define a tile and add it to tileXML.
var tileNotification = new Windows.UI.Notifications.TileNotification(tileXml);
Windows.UI.Notifications.TileUpdateManager.createTileUpdaterForApplication().update(tileNotification);