The Jehovah's Witnesses Discussion Forum is a very active group with some very thoughtful researchers. For reference purposes, here are some of the better discussions of the Jehovah's Witness blood policy.
The Watchtower Society is Wrong on Blood
41 Questions About the Watchtower Blood Ban
The Watchtower Stance on Blood is Not Biblical
My Letter to the Editor Concerning Emma Gough's Death
Death Statistics Due to the Watchtower Blood Doctrine
Blood and Organs
Blood Transfusions-Eating Blood?