First off, when I read Corporal Punishment it makes me think of the Armed Forces giving punishment to bad soldiers or something.
Ok, so I don't have kids. My viewpoint is from my childhood, my opinions, and what I've read.
In my childhood I was only spanked once in my life (that I can remember). I'm not sure if it was a great thing to do, but my dad smacked my butt really hard and that was it, I shut up and acted way better. I can still remember that pain radiating through me... It was painful and scary. It pretty much put the fear of God in me.
As for myself, I'm not sure about spanking. Its been a tool that parents have used for years and it seems to work. It all depends on your parenting style and your kids behavior/temperament. I wouldn't think I would like to spank my kid, but if nothing else is working I think I might try it.
As for people equating spanking to abuse, that's way different. I have read the horrible true life story of the author of "A Child Called It". That whole true series of books was the most heartbreaking, disgusting thing I've ever read. To think a mother would punish and treat her child so horribly is just unthinkable to me. But that's the thing, the difference. Most parents can tell the difference between a swat on the butt to correct a child's bad behavior and when it turns to abuse (using objects and harsher treatment than is necessary). Its the parents who use such harsh treatment, not understanding that humane difference, that are the issue. They have a serious problem within themselves (mental, behavioral) that turns a swat to unnecessary punishment.
You can't really associate these things together, its too extreme. Every situation has to be looked at separately to see if its a spanking or abuse.