I have heard both pronunciations, and I'm not sure that the creek was the dividing line. I have friends in Virden that pronounce it Muh coop un and others that use Muh goop un. My parents lived on the west side of the ITS tracks and said Mu coop un, and my wife's parents lived on the east side of the tracks and said Mu goop in. Both are common useage. toh may toh . . . toh mah toh LOL Jack Cox