This is something i have discussed in length with a variety of people, including ministers and other intellectuals.
I, personally, do not agree with slavery.
However, I don't know if we can say God would be against it, as in several instances in the bible he ordered the Hebrews to take slaves from the people they conquered. And yes, the Hebrew word used means slaves, not servants.
It was common practice to take slaves from conquered peoples until the rise of "western" civilization after the dark ages.
Don't flame me now, I said I'm against slavery, I'm just throwing this thought out for consideration.