With the death of Osama Bin Laden I've seen many people "rejoicing," and then we see some Christians complaining that we should not be rejoicing over the death of anyone. I believe Clarence Darrow (originally attributed to Mark Twain) sums it up the best:
"I have never wished a man dead, but I have read some obituaries with great pleasure."
Plus we are reminded of what King Solomon had to say:
All things have their season, and in their times all things pass under heaven. Eccl 3:1
A time to kill, and a time to heal. A time to destroy, and a time to build. Eccl. 3:3
A time of love, and a time of hatred. A time of war, and a time of peace. Eccl. 3:8