The people working on the lung-cancer screening issue are very aware of the bias sources inherent in screening studies. They try very hard to avoid the mistakes made with other 'magic screening pills' such as mammography and PSA.
I don't think it is 'big news' yet. 'Big news' would be the 5 year result of a study comparing lung-cancer (and lung cancer diagnostics) specific mortality of the 'screened' vs the 'unscreened' group of long-term smokers.