Its football!
Nike Mercurial Vapors, most recently against Brazil in the Confederations Cup he wore the Mercurial Vapors IV, but has also worn Mercurial Vapor V's and the yet to be release Vapor Superflys.
Because he is American
He was number 21 until recently he changed to number 10 which is suppost to be worn by the playmaker.
Landon Donovan isn't captain of the US National Team, Carlos Bocanegra is captain.