The Daily show is a lot like a breakfast cereal, good as a part of a balanced news diet. Yes, relevant. The reason its relevant despite being a comedy show is that a lot of news shows are poor sources of information. News shows have shifted from delivering journalism towards delivering propaganda. The Daily show profits from the poverty of serious news shows. Plus people love joking the 'Weatherman' and the news anchor with their continuous steely smiles, courageous voices and legal eagle poses.
There was actually a study that showed viewers who got most of their news from the Daily Show were better informed than viewers who got most of their news from FOX.
That's probably because they actively look for problems with the 'News' and tease the channels over the problems. It doesn't mean that they cover all of the news that the news channels miss. For that you'd have to actively look for yourself.