<i>...to my knowledge there's been very little success in finding any early childhood characteristics that have a strong positive correlation to adult success...</i><p>The Stanford Marshmallow study is one that springs to mind - delayed gratification in children correlates strongly with adult success:  <a href="http://www.sybervision.com/Discipline/marshmallow.htm" rel="nofollow">http://www.sybervision.com/Discipline/marshmallow.htm</a><p>Of course, one of the <i>really</i> interesting conclusions of that study was that children can <i>improve</i> their capacity for delayed gratification through practice.