This was a scary hit from the Blackhawks victory Friday night over the Red Wings.  Niklas Kronwall is the tattooer, Martin Havlat is the receiver.  YouTube user crazieman76 summed up the legality of the hit and penalty ruling nicely:

Rule 56 – Interference – The last player to touch the puck, other than the goalkeeper, shall be considered the player in possession. The player deemed in possession of the puck may be checked legally, provided the check is rendered immediately following his loss of possession.

56.4 Major Penalty – The Referee, at his discretion, may assess a major penalty, based on the degree of violence, to a player or goalkeeper guilty of interfering with an opponent (see 56.5).

56.5 Game Misconduct Penalty When a major penalty is imposed under this rule for a foul resulting in an injury of an opponent, a game misconduct shall be imposed.

In my opinion, I thought it was a clean hit, but technically Havlat never touched the puck. So, the refs did make the right call.