Those that may be new to live tournament poker may not know that it is against the rules to talk about your hand truthfully before showdown. For example, if you are on the turn and getting ready to bet or call a bet, you cannot tell a person what you actually have. If you were to tell a player that you have a king and then show a king either at showdown, or at any point, then you would receive a one-round penalty.
This rule was just explained to a table by our floor staff. After hearing the explanation, a player stated, "In poker, it's OK to lie, but it's not OK to tell the truth."