Looks like MS are going for compatibility as a real selling point with the Series X. A good move considering how many games people will have and they say there will be improved performance with the older games too. Not sure about "the most powerful" line though.
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Xbox Series X: The Most Powerful and Compatible Next-Gen Console with Thousands of Games at Launch - Xbox Wire
Gaming leaves an indelible mark on all of us. From the epic stories and universes we experience playing as our favorite heroes, to the heat of intense competition, victory and defeat. Through the shared accomplishments we achieve as a worldwide community, gaming brings us together. Thousands of...
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