http://ratings.fide.com/card.phtml?event=4101588
Since January 2007 (when they started keeping records), Vladimir Kramnik (currently #3 in the world) has never won a game starting on black. It seems to be much more difficult than I expected for top players to win starting second: most of the other top players seem to be about 40% more likely to win starting from white, though there is a surprisingly amount of variation, with some players such as Viswanathan Anand ending up about even (wins 29% on white vs. 28% on black).