As the media continues to create stronger icon status for people in the news, it is not surprising that lay people are dreaming of them as well. It is not at all unusual for people to think they "know" particular public figures and so to experience them in a dream. Dreaming of any particular celebrity often reveals a fantasy for friendship or romance. These dreams may also show a sense of being a peer or equal to that celebrity as if to say, "I can do that, too." A second aspect of this phenomenon is living vicariously through a celebrity. In this instance, people will assume a peculiar sense of participation with a public figure's success and notoriety.
Another variation of this is becoming a celebrity yourself. This may include performing with other celebrities while achieving your own icon status. This kind of notoriety may be showing you your own giftedness (or sense thereof) in a particular area, or it may be intended to encourage you to pursue a higher ambition for yourself.
Of course, because today's media completely inundates the public with images and rumors of celebrities, they may appear in your dream simply as extraneous static.