On the Joseph Smith Papers site you can find a pdf with side-by-side comparison versions of changes between the 1981 and 2013 editions of the Doctrine & Covenants (D&C). Most notable of these changes are the addition of headers to the two official declarations:
The Illinois Anti-bigamy Law enacted February 12th, 1833 clearly stated that polygamy was illegal. It reads:
"Sec 121. Bigamy consists in the having of two wives or two husbands at one and the same time, knowing that the former husband or wife is still alive. If any person or persons within this State, being married, or who shall hereafter marry, do at any time marry any person or persons, the former husband or wife being alive, the person so offending shall, on conviction thereof, be punished by a fine, not exceeding one thousand dollars, and imprisoned in the penitentiary, not exceeding two years. It shall not be necessary to prove either of the said marriages by the register or certificate thereof, or other record evidence; but the same may be proved by such evidence as is admissible to prove a marriage in other cases, and when such second marriage shall have taken place without this state, cohabitation in this state after such second marriage shall be deemed the commission of the crime of bigamy, and the trial in such case may take place in the county where such cohabitation shall have occurred."
Revised Laws of Illinois, 1833, p.198-99
This runs contrary to what is declared in the new edition of scriptures, which are now available in electronic format, by putting the date of polygamy practices being illegal as early as 1833. One possible defense is that the scriptures state that the U.S. government made it illegal beginning in the 1860's and that this was the Illinois State government. According to the Church's Articles of Faith:
We believe in being subject to kings, presidents, rulers, and magistrates, in obeying, honoring, and sustaining the law.This would therefore have still made polygamy impermissible. Even with their move to Utah, which at the time was owned by Mexico, it was illegal under Mexican law, thus making it illegal throughout the entire history of the church.
As for blacks and the priesthood, this heading is more ambiguous of the past, than an actual clarification or justification. At the very least we can say it is finally an admission to its previous bigotry and discrimination that had previously prevailed in the Church towards blacks, but it denies knowledge of why, or how this could have come about.
Being more ambiguous is a theme in the changes made at least in the D&C, where definitive's are traded for mere possibilities. One example is in D&C Section 2:
1981: An extract from the words of the angel Moroni to Joseph Smith the prophet,...to
2013: An extract from Joseph Smith's history relating to the words of the angel Moroni to Joseph Smith the prophet,...References to History of the Church (HC) have now been redone to say Joseph Smith's History. It has turned the text from declaring facts to voicing opinions.
Print versions of the new scriptures are expected to be available in August, 2013. Elder Neil L. Andersen of the Quorum of the Twelve Apostles has said:
“This new edition incorporates adjustments that will be a blessing to Church members in years to come, but members should not feel that they need to purchase a new set of scriptures, particularly since all of the adjustments are available in digital formats at no cost. Changes to the scriptural text include spelling, minor typographical, and punctuation corrections.”There has been no announcement thus far concerning translations of scriptures into other languages based off of changes made in the 2013 English edition.