What is the Joseph Smith Translation?

Pastor Bryan recently preached a sermon were he Acts 13:48 and I warned that we might not be comfortable with that verse.  Later, he learned that the Joseph Smith Translation re-wrote the verse to change it's meaning and make it more palatable to LDS theology.  While discussing this with someone, a question was raised: "What is the Joseph Smith Translation (JST)?"  Is this a translation or is it something else? Hint: it's something else.  

In this Redeeming Life Q&A video, Pastor Bryan looked at Acts 13:48 that reads "And when the Gentiles heard this, they were glad, and glorified the word of the Lord: and as many as were ordained to eternal life believed" (King James Version, KJV) but the JST reverses the last clause to read, "and as many as believed were ordained to eternal life."  What are we to think of this re-write?