No, his hand isn't dead. Hands are actually very hard to kill. The hand plays out as normal and your opponent may or may not get a penalty at the discretion of the tournament director after
the hand is over.
Here are the rules on it (emphasis added):
ROBERT'S RULES, IRREGULARITIES, RULE 12:
12. Procedure for an exposed card varies with the poker form, and is given in the section for each game. A card that is flashed by a dealer is treated as an exposed card. A card that is flashed by a player will play.
To obtain a ruling on whether a card was exposed and should be replaced, a player should announce that the card was flashed or exposed before looking at it. A downcard dealt off the table is an exposed card.
ROBERT'S RULES, TOURNAMENTS, RULE 22: (http://www.homepokertourney.com/roberts-rules-of-poker.htm#SECTION_15_-_TOURNAMENTS)
22. Showing cards from a live hand during the action injures the rights of other players still competing in an event, who wish to see contestants eliminated. A player in a multihanded pot may not show any cards during a deal. Heads-up, a player may not show any cards unless the event has only two remaining players, or is winner-take-all. If a player deliberately shows a card, the player may be penalized (but his hand will not be ruled dead).
Verbally stating one’s hand during the play may be penalized.
and just for the lulz...
POKER TOURNAMENT DIRECTORS' ASSOCIATION RULE 42: (http://www.pokertdablog.com/PokerTDABlog/?page_id=107)
42. Exposing Cards. A player who exposes his cards with action pending may incur a penalty, but will not have a dead hand.
The penalty will begin at the end of the hand.