Something i actually don't get about the ending.

Who actually killed Tony?? and why in the world would Tony come out of hiding immediately after killing the head of a family? It makes no sense, that's when its probably the most dangerous, of course there are going to still be dissidents and people who want to kill him for what he's done so why would he come out of hiding? Also i kinda wish they would of shown the aftermath though, wanted to see the look on Carmela, meadow, and AJ's face when he got shot LOL.