I didn't notice any upstaging. I thought that the Coalition forces successes were quite well covered by all the media, both Fox and CNN. Due to a quirk in what I do for a living, I am able to track what's on both of these all day. When the Coalition advanced, all the media outlets covered it. In the context of Coalition casualties numbering over a hundred, and especially in context of the hundreds of thousands of Coalition troops who are not casualties, how important is the Jessica Lynch story anyway? I wouldn't change the fact that she was rescued--but history shouldn't attach much significance to it. The signal coalition success in aerial bombardment of Iraqi positions saved coalition lives wholesale, but received similar report time as the rescue of that single damsel in distress.
We were all interested in hearing about Private Lynch--but the fact that we were interested in that story does not change the fact that you should have known at the time that the defeat of the Iraqi army was more important. We just didn't know the names of the coalition troops who were not injured or killed because of it--whereas Private Lynch has a pretty face.
I thought at the time that the rescue of Private Lynch was overblown in the media. However, what I didn't notice was any difference between Fox, CNN, or the various broadcast media on how that was covered vs. how the progress of the Coalition forces against the Iraqis was going. I see no evidence of bias, liberal or otherwise, in the way the different media handled the story.