At the first ATL DO, when the question of whether or not the phantom upgrades that NW had implemented in the last year or so came up, Jeff R indicated that he thought it was a great idea and a great marketing tool and that they would look at ways to bring them back, maybe. And Bob S, who had implemented them at NW indicated that he had taken some grief from employees whose pass travel was more likely to be in coach because of the phantom upgrades of platinums (and some golds, I guess).
Haven't heard much since then. I have been fortunate to snag some international opups when the back has been oversold.