The new world No.1 --- Rafael Nadal

"After Wimbledon, Nadal extended his winning streak to a career-best 32 matches. He won his second Rogers Cup title in Toronto and then lost in the semifinals of the Western & Southern Financial Group Masters in Cincinnati, Ohio. These results combined with Federer's early round losses in both of those tournaments guaranteed Nadal the World No. 1 ranking on August 18th, officially ending Federer's record four-and-a-half year reign at the top."

---Wikipedia