It matters in the sense that a media conglomerate can't consistently act in concert to effect cultural change, which was the original question. But I think you're being insufficiently cynical if you don't think the news properties are there to put money in the pot, too.
Before Fox News was launched, the overwhelming sentiment among conservative Americans (who, let's not forget, make up about half the country) was that other news sources had a liberal bias. It was an obvious opportunity to exploit.
In the UK/Australia, News Limited has been heavily involved through its newspapers in dictating government policy. For example the "boat people" issue was very much promoted in Australia and in the UK there are countless examples of governments capitulating on policy at the behest of the News International papers.