The question should be “where do you (asasass) want the center of the background-image to be?” The default position is top left. While it may not seem to make a difference with this small image, the eye tends to notice such things as a page is zoomed or as a large, fixed size image overflows the edge of its container. Either way, it’s your call.
To test your fiddles, add this one line to the <body> element’s CSS. background-repeat:no-repeat;