Ethics: What do you think about sites that show people what they want to hear?

This is an ethical question. I've noticed lately that some of my friends have been telling me sending me stuff from Huffington Post or Daily Kos or Fox News or basically websites which offer a highly biased point of view while censoring or strongly downplaying other points of view. I'm working on a project which allows people to personalize their information and find information that's relevant to them. Then this ethical question dawned on me. I have a personality which encourages me to search the world and find different viewpoints and find the truth. Unfortunately, I find a lot of other people I find have the opposite. They want to find information that suits their thought or their preconceived notions and reject anything that opposes that until reality hits them on the head with a brick. Even then, they still want to defend their views and use strongly biased sites to help strengthen it. As I go further in my project, I'm realizing I'm helping create a way where they can completely ignores everything about the world and thus create a place which tells them ONLY things "they want to hear" even if what they want to hear is wrong. I'm worried about this ethical question. I mean, there's a ton of money to be made in the "Tell People What They Want To Hear" space but I'm worried about the long term consequences of this. How do you guys figure out an ethical questions like this?