Why have a loop? 
sub nn {
my@x=@_[0,1];@_=sort{abs$x[0]-$x[1]<abs$a-$b or@x=($a,$b);$a<=>$b}@_;@
+x
}

[download]
(75...)

UPDATE
MeowChow pointed out that the parens for the arguments of abs were not needed. That cut out 3 characters. Plus by reversing the order of the comparison I managed to substitute or for and, saving another. That makes it 71...

UPDATE 2
This is sick and slick. 

sub nn {
()=sort{abs$_[0]-$_[1]<abs$a-$b or@_=($a,$b);$a<=>$b}@_;@_
}

[download]
Enjoy verifying that I am perfectly safe in using @_ as my temporary array. I think that 58 is the best I can do...

UPDATE 3</B
petral sent me a /msg explaining how to remove 3 chars from that solution. I would like to see him post that since it was his idea, but until he does I want to note that that solution can be beaten.

In reply to Re (tilly) 1: (Golf) Nearest Neighbors by tilly
in thread (Golf) Nearest Neighbors by MeowChow

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