Yes, bin Laden was murdered

Here's another story which appears to clearly state that Osama bin Laden was murdered:

http://news.yahoo.com/mystery-seal-could-settle-bin-154506551.html

If the rules of engagement were "shoot him dead before he can reach for a weapon", that sounds like premeditated murder to me. At best, it's the level of "bravery" exhibited by police who shoot dead a crippled man in a wheelchair because they are afraid of his scissors:

http://sainthoward.blogspot.com/2013/03/cops-are-afraid-of-scissors.html