Unfortunately, there is no current option for a simple delay between iterations, but instead you can add another stop with the same values (as I commented) and increase the duration:
@keyframes fade {
0% { opacity: 0; transform: rotate(0deg); }
10% { opacity: 1; transform: rotate(360deg); }
50% { opacity: 0; transform: rotate(360deg); }
100% { opacity: 0; transform: rotate(360deg); }
}
.selector {
animation: fade 6s ease-in-out infinite;
}
Demo at http://jsfiddle.net/PW8Ur/2/
If you need a control script when you want to restart the animation, you can watch: http://css-tricks.com/restart-css-animation/