David Foster Wallace, author of the novel Infinite Jest and other books that have gotten a lot of attention over the past few years, has just published an essay about Roger Federer in The New York Times. I recommend it; along with being a good description of Federer himself, it is an excellent analysis of the current situation in men's tennis.
(If you can't get to the article, sign up for free access to the NYT. If the article is more than a week old and hence in the archive, then you can access the archive if you subscribe to the NYT or to the International Herald Tribune. If you cannot get to the article otherwise, I did download it, so you can ask me to send it to you.)