First and foremost, rest in peace Mr. Park, you passed from this earth doing something you love. My thoughts and prayers are with your family and friends. Also my sympathies to Markko Martin, I cannot imagine what you are going through right now.
Now, as to everyone arguing over safety, it has be understood that physics is physics and universal laws are inmutable. Regardless of the sport, when people push themselves and in most instances their equipment to the limit, failure is bound to occur. That is not to say that I wish ill of anyone participating, just that injuries/fatalites are a part of any sport. To regulate the competiveness out of the sport kills said sport, and I honestly doubt those who have paid the ultimate price wish to see their legacy as the death-knell of that which they love.
People have died piloting planes, cars, mo-bikes, boats, bicycles, horses, and even in foot races people have died, however most governing bodies can understand that as the limit is pushed, eventually the limit will push back. If my memory serves correctly the FIA is already set about standards to limit the speed of Rally Cars for '06 and beyond by taking away the turbos, making the diffs mechanical as said before and limiting the engines to a transverse mounted inline-4 not to exceed 2.0 litres. All well and good, but given that F1 engines are currently at 3.0 litres and capable of 900ps +/- , I don't really see how killing the turbo will truly reduce speeds in the WRC. All I can see is that the engines will rev higher on shorter strokes, so that even more wheel spin will be needed to get through corners to maintain speed, instilling even more opportunites for corners to go badly. I do not have any great answers to simply solve the issue an I doubt that any one person or even governing body does, but I have rarely seen the FIA make the correct call. All I can say is now is not the time to toss the regulations for the WRC and start from scratch. Yes, a person has died competing, but that does not instantly make the stauts quo unsuitable. Had Michael Park died as a consequence of FIA Regulations, yes, let's take it to committee as of right now and fix the issue, but as far as I can tell, it was just bad fortune that got "Beef", let the man rest, let his family greive, but please don't kill that which he loved enough to lay down his life for.