Osama Bin Laden received the earthly justice he deserved for his murderous ways, just as Romans 13 describes. We can be sure he is receiving ultimate justice by God's judgment as well.
I am appreciative that Bin Laden received this justice and will be personally unable to continue perpetrating more atrocities. I am grateful, in this instance, for the government bearing the sword and carrying out God's wrath on the wrong doer. (See Romans 13:1-5)
I am very cautious to be happy or celebratory about this event. We do see celebrations when the enemies of God are killed in Scripture (Goliath, being one example), but the focus of celebration is on God's greatness more than personal vengeance.
To be honest, I am no different than Osama Bin Laden, except for the grace of God in Christ. The only thing that stops me from being a heinous murderer is God's grace. I am morally bankrupt apart from God's grace. There is no righteousness in me apart from Christ's imputed righteousness by faith. My heart is black if not for the regeneration of the Holy Spirit. I'm still a terrible sinner, even despite being a recipient of God's amazing grace in Christ.
Justice, good. Self-righteous gloating, bad.