This reminds me of all of those services for annotating the web, but as far as I know none of those have gotten significant traction. Perhaps everyone just pref

This reminds me of all of those services for annotating the web, but as far as I know none of those have gotten significant traction. Perhaps everyone just prefers referring to things by using just normal language, instead of a special tool to select something explicitly. If StumbleUpon included an annotation feature, maybe it could catch on.