USCF Chess Rule Book, chapter 11: Blitz Chess, p. 120, art. 7d: "[A game is won by the player:] 7d.) Who, after an illegal move is completed by the opponent, takes the king (if the king is in check) or claims the win and stops the clock, before the player determines a move and provided the player has sufficient mating material as defined in rule 7c. A player who moves his king adjacent to the opponent’s king and then attempts to claim a win under this rule based on the opponent’s failure to notice the check shall lose the game."
The United States Chess Federation has a variation that tournament directors can use. If a player intending to castle touches the rook first, there is no penalty. However, if castling is illegal, the touch-move rule applies to the rook. This variation does not have to be announced in pre-tournament publicity but should be announced at the start of the tournament. "Rulebook Changes"(PDF).
