I write this in response to Graeme Swann's rival "ball of the century".
Looking at the balls side by side and I believe a couple of things become obvious.
1. The movement of Swann's ball down the leg side of the batsman is purely from the angle his arm would naturally push the ball upon release. Warne's ball is bowled from the inside arm that would naturally push the ball either straight, or towards the off side. The movement down leg is created by very pronounced, and very late drift due to the heavy rotations on the ball.
2. Swann's turn seems to look like more of a deviation than actual spin due to the already quicker nature of his action. Surely a ball that had spun on it's own merits would produce similar drift as Warne's ball. I suggest that Swann's ball hit a crack or protrusion to create the movement. Warne's on the other hand would have spun on ice as indicated by the drift.
Apart from that Warne's ball was his first in tests on English soil and cultivated a deep seated fear of first his bowling and then Australian for decades to come.
Me thinks this only spin from English media to hype the upcoming series.