TD is the leader in Spurs. PP is the leader in Celtics. If you want to compare leadership, let's wait and see Rondo and Parker become the real/sole leader of respective teams first.
Don't get me wrong, I do like Parker and Rondo, and love their games.
Patrick Ewing, Karl Malone, Charles Barkley, and John Stockton, have 2 things in common - 1. Great players 2. No rings. Scotti Pippen is a great player himself, but he's not better than those 4 players, be it skills, impact, or leadership.