Until Microsoft announces the next Xbox console, we're going to speculate. We can't help it. Kotaku has posted the latest NextBox rumor stating "multiple sources close to the project" have told them the current nickname is "Durango." I'm not crazy about this codename and to be honest it make me think of the Canyonero.
As is the tradition, codenames and nicknames don't mean anything when it's time to officially announce a console. Remember when Kinect was Natal and the Wii was the Revolution?