Kim's pulled out of Beijing with a foot injury. She had a mole removed and it hasn't healed all that quickly. And in case people call bullshit, she savily preempted it. So no Serena or Kim in China.
Though, can I just say this: You've just won the US Open. You know you have a mandatory tournament to play in three weeks. Do you really think it's wise to do anything surgical to any part of your body, let alone THE BOTTOM OF YOUR FOOT, during that window? Just a thought.