apparently, neo is no longer
neither is smith.
if either were alive, the matrix would unbalance and destroy itself. just as the oracle said it would.
as for peace, well its not something the architect is used to. maybe it wont last, maybe it will.
due to the final scenes, it seems the matrix still exists, but will have to be changed now that peace has come about.
do you realize that all of the characters in the final scene are programs?