You've hit on one of my favorite topics! I'm a big fan of Tiger Woods. I think he would have been every bit as famous if he were white. There are several reasons for this.
1. There have been black golfers, asian golfers and every other type of golfer on the PGA tour. Can you name me another black golfer? They have been rare, but the colour barrier was broken in professional golf many years ago.
2. I remember commentators talking about Tiger Woods being black for maybe the first year that he was on tour. Then nobody talked about it anymore. It stopped being interesting. What became interesting was the fact that he is the most incredible golfer that anyone has ever seen. As for Tiger Woods, he said "I don't want to be known as the best black golfer. I want to be the best golfer period."
3. He is the best golfer ever to play. He hasn't topped Jack Nicklaus' record of 18 "majors", but he will. People are interested in greatness, not blackness.
4. There are many aspects to Tiger's story that are fascinating, such as: his relationship with his father (who was a green beret in Vietnam, and who passed away in 2006); the Tiger Woods foundation, which has contributed tremendously to various causes; how early Tiger got started and how good he was from the beginning; how tremendously hard Tiger works, how his practice schedule is brutal, he is arguably the hardest working golfer on tour, and is extremely critical of himself.
5. Tiger will be the first athlete to earn over a billion dollars.
That Tiger is part black is irrelevant. People would admire his ability, work ethic, and philanthropy no matter what his race. I also happen to admire him because I get inspired by champions, the way they think, the way they push themselves, and the way they rise to the moment. Tiger embodies these traits.