Goku would Crush Superman in a duel....

http://answers.yahoo.com/question/index?qid=20100803095920AATrsJP

Goku, because his power is more than anyone that Superman has encountered with so much effort. Even less powerful characters like Piccolo could destroy the moon from Earth and still be standing.

SS4 Goku fired a blast that sent an enemy straight into the sun with ease from Earth (practically)

Clearly Goku has more power and can move at full speed without accelerating unlike superman who needs a minute or 2 to reach top speed but only when covering so much distance.

http://answers.yahoo.com/question/index?qid=20071104104004AA2PTef

http://lounge.moviecodec.com/testing/goku-vs-superman-17280/

bumped cause geek question of week got me interested in this topic again.