Coming from the perspective of an everyday normal person, I do not think sensationalism harms the reputation of a news source. I don't think regular people (people who do not have a strong background in media) even think twice about sensationalism. They see a news story and are attentive sometimes because it's sensationalised. I don't think they realise it is, and so they wouldn't think otherwise about it not being reputable. I know I can relate to this because prior to being so engaged in the media world I would have not picked up on such issues and sensationalism was not really apparent to me.

News sensationalism to me just means you are extravagant when presenting a story. There is also an element of drama which I guess is supposed to draw viewership and attention. I really don't have any favourite examples because I don't watch news a lot, and if I do I'm giving attention to the detail not to how the story is presented.