The Joseph Smith Translation of the Bible: A Panel - Very valuable reading on the subject covering different areas and commentaries. These guys tend to talk about the *themes* that were inserted or added by the JST a lot.

1 Nephi 13:26 - many important parts were removed from the Bible

2 Nephi 29:10 - do not suppose that the Bible does not contain all of God's words or that he has not caused more to be written