I still havent seen a onehanded backhand push Nadal around, sure Federer and Blake can sometimes run around with their forehand but guys like Haas and Gasquet are more reliable on their backhand. So far I havent seen players with one handed backhands push Nadal around with their backhand like lets say Djokovic, Murray and Simon can do with their two handed backhands. I dont expect Haas to do it against Nadal, he will lose badly straigtht sets, I really hope I am wrong but as the prophet Deathclay said the one handed backhand is kind of a dying breed.
There are no players under 22 that I know who play with a one handed backhand, please inform me if I am wrong and there still is a future for the onehanded backhand.
The promising and stylish youngster, Grigor Dimitrov, has a one handed backhand but the kid is only 17 so it will be a while before anybody really hears about him. He is a very good prospect though and you can watch him play Kontinen in the junior Wimbledon final 2008 on youtube.
Interestingly, Kontinen had a 100% statistic on S&Ving on the 1st AND 2nd serves by at least the end of the 1st set, AND has a one handed backhand. Ok I know both of these guys are super young but still, it shows that young promising tennis talents are not still just willing to try and beat the best with a one hander but also are willing to S&V more.