Smackdown
(Note: I really should read both pages of the topic before posting. I see that most of what follows has already been covered.)
Saw a similar episode in the playoffs several years ago; Flyers and Redwings, or maybe Flyers and Devils. At any rate, as the puck cleared down the ice and the referees skated with the action, the last people left on one end of the ice were the goalkeeper, another player of indeterminate position--Doug Sheppard; I remember the incident, but I'm not that big a hockey fan to remember Sheppard's position, or anyone else's name--and a Flyer. The Flyer skated up behind Sheppard and took a baseball swing with his stick. Sheppard was knocked instantly unconscious and swayed on his feet, skating slowly for about ten feet until he collapsed in a heap on the ice. No penalty, and therefore no fine or suspension.
Remember that there has already been one hockey prosecution in recent years, stemming from an incident in Vancouver, as I recall.
Throughout pro sports, I think that if you intentionally injure someone, you should be suspended at least as long as it takes for them to return to the ice. If you end their career, you also end your own. Hockey would have some difficulty with this; baseball would suffer as Pedro Martinez could no longer arbitrarily try to kill people in the box; American football could actually profit from such a rule.