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Hi Steven, To my understanding, Bing and Yahoo are essentially the same thing these days; they're the same engine, so that's good news I'm always dubious of "complete list of ranking factors" type blog posts, but check out this post from Matthew Woodward. Beyond the intro, most of the top section is quite irrelevant to you here but scroll down and you'll find a bunch of great resources that might highlight something you can do to see you ranking better. Fixing up that outdated sitemap is going to be a good idea either way. Hope that helps!