Those aero grooves make the ball swerve like a curveball
David James is not impressed by the Jabulani:
“The ball is dreadful,” James said. “It is horrible, but I suppose it is horrible for everyone. You saw that from Frank Lampard’s free-kick in the first half against Japan, which dipped wickedly, so it will be interesting.”
The growing list of critics include:

Hugo Lloris: “This ball is a disaster.”
Fabio Capello: “Completely different.”
Júlio César: “Something out a of a grocery store.”
Giampaolo Pazzini: “A disaster.”
Claudio Bravo: “It was made to prejudice goalkeepers.”
Iker Casillas: “Appalling”
Gigi Buffon: “It is very sad that a competition so important as the World Cup will be played with such a horrible ball.”
Luís Fabiano: “Supernatural”
Júlio Baptista: “The ball works against strikers and goalkeepers.”
Joe Hart: “The ball has been doing anything but staying in my gloves.”
Morten Olsen: “We played with an impossible ball and we need to get used to it.”
Robinho: “For sure the guy who designed this ball never played football.”