I don't know about this. I don't like hearing about the death of any person. I'm a pacifist at heart, I guess.
The only thing I can think of is he was a living human being. He was misguided and a fool but he was still alive. Yes, his actions caused the deaths of 1000s of people, but does that give anyone the right to take his life and the lives of those around him or associated with him?
Revenge is petty and childish, makes us as bad as them and ultimately doesn't make a bit of difference. In fact, it often makes things worse. Osama bin Laden is dead. The American army (thus the American government and the American people) killed him. Someone is going to want to take revenge on that. And when they do, where will we be? What will happen? Revenge. Again. And again, and again... It will never end, because that is what revenge does. It destroys. It destroys people from the inside out. It destroys nations and, taken to extremes, destroys the earth we live on.
"What about all the people he killed" you ask? Well, what about all the people the American and British armies killed while looking for him? Are those deaths not as important, do they not matter?
I've had my share of pain, my share of loss. Revenge never makes the pain less, it never brings back what was lost. The best thing to do is learn from it, move on, and LIVE. Live your life to best of your capabilities. Because that is what will make this world a better place - life not death.