I don't watch the news much, and I had to go look this story up. From what I gather, he admitted to embellishing his experience on a helicopter, and is accused of embellishing his experiences post-Katrina. I also got the impression that he never told that helicopter story on the news itself, but rather on other shows like talk shows. I haven't read that much this morning, but I don't see him being accused of changing facts of stories not related to his own experience, or being accused of lying about his helicopter experience on NBC News.
Seems like a guy who got caught up in wanting to think, and wanting others to think, that he experienced some of the stuff that he reports on daily. I don't know about his life and career, but I imagine that a lot of it involves sitting in an office or behind a camera, reporting about what other people have done. I'm not that judgmental about that, but like I said, I don't watch the news that much and don't have experience with him talking about those stories - just what I read about this morning.