The introduction of the instant replay system at the 2006 U.S. Open also focused attention on the big screen TVs in the two main show courts.  For example, many players watched themselves on the big screen during the regular replays of each point in Arthur Ashe stadium.   During her semi-final against Justine Henin-Hardenne, Jelena Jankovic seemed to glance up at the big screen regularly between points and also on the changeovers between games.  Top players have obviously seen themselves on TV many times.  So why look up at the big screen? Sometimes, maybe it's unconscious positive reinforcement after a player has hit a good shot.  Other times, maybe it even helps a player correct something after a bad point in the middle of a match.  A possible ancillary effect of the new TV screens on show courts will be that players pick up a few quick tips all by themselves in mid-match!