Which will be the top 5 most important Cabinet positions in the next four years? Why?

Obama's Cabinet: Who's in, who's out?

http://www.cnn.com/interactive/2012/11/politics/obama-cabinet/index.html?hpt=po_c2

RIP:
Mayor Ed Koch http://www.cnn.com/2013/02/01/opinion/kaiser-ed-koch/index.html?hpt=po_c2