Cofty's essay on the matter is quite on top of it from the other perspective as well, that of mainstream Fundamentalism and even the conservative movements in Protestantism. (You should write professionally, Cofty...about anything. You are good with words.)
Jehovah's Witness have built their idea of God based on this foundation, making God a deity that has such high standards that physical death and bloodletting are the only way to satisfy His judgment and quench His demands for atonement. Their idea that God demands a physical sacrifice for sins comes from the misapplication of Hebrews 9:22, namely that the Mosaic Law was interpreted by this Christian statement.
The problem is that there are many ways to read Hebrews 9:22, and only one fits the accepted Jewish interpretation. Jews don't believe that animal sacrifices are the panacea to remove sin. As several rabbis I know have explained it to me, "If we believed that we would have rebuilt another Temple as soon as we could."
The Jewish sacrificial system was about thanking God for life through food. Since food sustains life, some of what was eaten was "given back to God" to say "thank you" (though this portion usually ended up being reserved for the priests at service in the Temple). Blood was poured out of animals because the ancients believed that the very life force of beings existed within it. The life force of a creature belonged to God, so it had to be properly given back through the sacrificial system. To this day Jews generally cannot eat hunted game because the idea behind kosher laws is that blood has to be sufficient drained to demonstrate that God is recognized as the giver of life. Rabbis generally are not widely available for all who hunt, therefore kosher law is generally viewed as broken if game is consumed, even today, unless it can be proven that the animal was slaughter and bled under the direction of a rabbi. The ancient sacrificial system, while concerned with religious worship, was largely in place for this very thing regarding keeping kosher.
"Today we have modern kosher butchering systems," one of these rabbis explained to me. "Now we can make sure Jews don't mishandle animal life or blood through rabbis on staff for just that purpose. But the idea that sin could only be erased by blood, if that was ever fully understood in the way Christians believe, was not of our making."
While blood was originally seen as a means of atonement via the sacrificial system, it was only one of the ways sins could be forgiven. As their theology progressed and Judaism evolved (and Jewish theology even has space for the belief that God evolves in His ways to), sacrificing animals as a means of atonement for sins was phased out. Already by the time of Solomon Judaism had begun to embrace the idea that personal repentance could do just as good or better than the offering of an animal's blood. (For a thorough Jewish explanation from one of their best sources, see Jews for Judaism: Leviticus 17:11.)
Simply put, the verse from Hebrews is often applied by some Christians, like the JWs, as if it expresses a Jewish view. The only way it can do this is if the verse is rendered something similar to this: "Indeed, under the law, it might almost be said that everything is cleansed by blood, and without the shedding of blood there is no forgiveness." (Revised English Bible) The author of Hebrews, if they had the Jewish understanding in mind, may have actually meant that sacrificial shedding of animal blood is such a rule of thumb in the Mosaic Law, so much so that it seemed that without blood forgiveness could not occur. The author of Hebrews then builds upon this as an illustrative symbol of Christ's sacrifice, but never states that this is a definitive law in itself. The Jewish Bible regularly testifies to the fact that God does not require blood and that repentance and forgiveness can and will occur without it for Jews.--See Psalm 50:13-15; Isaiah 43:23-25; Proverbs 16:6; Ezekiel 18:21-30.