Yeah, I saw that. She sometimes takes the racket back too high, IMO, on the fh side (not that my own fh is remotely close to being anywhere near as good as hers), which can create some timing issues. But also in that case it was tough because as either Cahill or Pam (can't remember which) said she was just flat footed after nearly every shot, presumably because of the knee problem. She would hit it and just stand still rather than getting back on her toes and recovering to the center of the court so when Cahill was talking about the tendency for players to load up on the back leg and drive through the ball can see where the knee issue would inhibit that.
I think Serena tends to hit the fh cleaner moving even closer to the baseline because it forces her to kind of cut down on the loop on the backswing and accelerate the racket through the shot faster. Looks like she tends to hold it for a second on the follow through sometimes - maybe to kind of emphasize the important of the finish. Also, she's so great at racket preparation - at getting the racket back quickly off both fh and bh sides - but sometimes it looks like she has it back so fast on the fh side she's almost forced to wait which can occasionally create a kind of double-clutching waiting for the ball, like the racket is there, she's ready and then she has to pause a split second because she's so early whereas with Federer, Nadal etc. it's more of a continuous swing. Love her her service motion. Cahill pointed out during Wimbledon that Baghdatis sometimes decelerates his swing on the fh side rather than accelerating when he is under pressure and said he was familiar with that as he used to do it too in his playing days. Have always wondered how various pros correct the stroke when they have an issue with it in the match. Once saw Laver speak at a clinic and he said whenever his stroke would go off in the midst of a match he would try to hit even harder and hit right down the middle to give himself a margin for error but hitting harder forced him to speed up the racket.