You also might notice a little lag because 0deg and 360deg are the same spot, so it is going from spot 1 in a circle back to spot 1. It is really insignificant, but to fix it, all you have to do is change 360deg to 359deg
my jsfiddle illustrates your animation:
#myImg {
-webkit-animation: rotation 2s infinite linear;
}
@-webkit-keyframes rotation {
from {-webkit-transform: rotate(0deg);}
to {-webkit-transform: rotate(359deg);}
}
Also what might be more resemblant of the apple loading icon would be an animation that transitions the opacity/color of the stripes of gray instead of rotating the icon.