FadeTo() on this selection (cloned and appended) not working?

Question

I'm new to jQuery and i'd like to fadeTo() this selection to give user feedback about data being fetched from the server:

// Loop on each array of object returned from the ajax call
$.each(v, function(i, obj) {
   current.find('.key:first').parent()
      .clone(true).appendTo(current)
         .find('.key').text(obj.key).andSelf();
};

I've tryed (without success) adding fadeIn('slow', 1) call after appendTo(current).