My brother posted as both guests. We both play the game, and he notices the same thing I did, but he wouldn't have posted because he doesn't play as much as I do, so he signs in as guest to add another voice to this issue. Sorry, I wouldn't have got him to do this, but this is really the only game I play, and I'm just so into it I guess, and I have really have noticed a change in the speed/difference of the gameplay against cpu between the current version and last version.
Currently I have 2 versions installed: the previous version for playing against cpu, and current version for playing online. Wish the play against cpu could be changed back to last version
I really think it was the Nadal-shot thing that did it perhaps?