What they aren't mentioning in the news blurbs is the context of Cap's death. The Marvel Universe has been going through a metaphorical story arc called
Civil War.
From what I gather, the government passed the Superhuman Registration Act
"to register all super-powered beings as living weapons of mass destruction and requiring all costumed heroes to unmask themselves before the government and subject themselves to federally mandated standards" (from
Marvel Universe).
Cap was the leader of the underground resistance movement, opposing the government's Superhuman Registration Act. The pro-government side is lead by Tony "Iron Man" Stark (and also includes a motley crew of super-villians hired by the government). Aside form those stating their neutrality, the Marvel universe was fractured into these two opposing forces.
Now, Captain America (the symbol, in this case, for the struggle to maintain civil liberties in the face of a restrictive government claiming that security requires a sacrifice of ideals) has been killed. Assasinated on the steps of the Federal Courthouse.
Also, this (from Wikipedia): "At the climax of a battle between Registration and resistence proponants, realizing that his fight against the Registration Act is endangering civilians, he removes and drops his mask to surrender as Steve Rogers. He gives the anti-Registration side the order to stand down.
As Captain America is led away, the Punisher picks up the discarded mask."