The correct way to do this is to iterate over the items in the d3 object and attach the handler to all of them:
list.forEach(function(elem) {
$(elem).on('change', log)
});
Working fiddle: http://jsfiddle.net/LbLjc/3/
If you are confident you only want the first one, you can shorten it to:
$(list[0]).on('change', log);