What in the world...?

My car was feeling a bit sluggish, so I opted to do a little tune up this weekend. I doubt the sluggishness was because of this, but look at what I found when I pulled on of my wires out! ..

http://www.imagestation.com/picture/...0/fc1f37b4.jpg
http://www.imagestation.com/picture/...c/fc1f37b1.jpg
http://www.imagestation.com/picture/...7/fc1f37a8.jpg

This is the only one that has corrosion, thank goodness. But that raises my question... How the hell did this happen? and is it negatively affecting my ignition?
The car seems to run fine, I just don't get it.. :?

corrosion sucks don't it. It may not cause trouble right now, but it will only continue to corrode further and further through that wire so deal with it now. It could have been from moisture, or if you washed your engine bay, or just a freak of nature. Either way, fix it now. Did you use di-electric grease on the wires?

it happens.
frankly, it happens WAY MORE with aftermarket wires.

Are those VITEK wires? I know a couple guys with them and they had the same thing happen to them and also Toucan wires.

tap dancing jesus! what in the hell? that happened to our 89' volvo