Celebrating bin Laden's death?

My daughter, a BYU photography major, was in Washington last night on vacation with her husband. When she heard about Osama bin Laden’s death, she grabbed her camera and went to the White House. Here is some of what she found:

The last one, I think, strikes the right tone. I’d like to know what you think. Is it OK to celebrate someone’s death? Or is it more appropriate to cheer a victory for freedom, but in a spirit of gratitude and with solemn remembrance of those who have died because of this awful man?
On her blog (where you can see more photos), my daughter said, “The atmosphere was jubilant, people were chanting, singing, cheering. While a bit disconcerting to see cheering over the death of an individual, I believe the intense emotion many feel understandably turned into this type of reaction – especially in an enormous crowd like gathered last night.”
What do you think? Is it understandable? Osama was the mastermind, but al-Qaida remains. Should we be more steely eyed and determined for the battles ahead?