I guess there will be lots of interesting little changes, but perhaps the most significant change in the new version of the NWT is overall readability. There were many, many passages of the old NWT that were virtually incomprehensible unless you had read some Watchtower commentary explaining what on earth they were trying to say. Take 1 Cor 7:36 in the old NWT for example:
But if anyone thinks he is behaving improperly toward his virginity, if that is past the bloom of youth, and this is the way it should take place, let him do what he wants; he does not sin. Let them marry.
What does that even mean?
But if anyone thinks he is behaving improperly by remaining unmarried, and if he is past the bloom of youth, then this is what should take place: Let him do what he wants; he does not sin. Let them marry.
Much better. They could have replaced "bloom of youth" while they were at it, but at least it's now in some recognisable form of English. This may be a particular verse that some on the Governing Body were keen to make crystal clear in their own interest for obvious reasons.
However they seem to have been more timid when it comes to improving the language of doctrinally sensitive passages. 1 Cor 15:29 for example remains pretty obscure:
Otherwise, what will they do who are being baptized for the purpose of being dead ones?
Say what? Come again?
Polishing the language in the Song of Solomon brings some interesting thoughts to the fore, as 2:3 more clearly becomes a reference to oral sex. Whereas the meaing might get lost in the overly wordy older version:
His shade I have passionately desired, and there I have sat down, and his fruit has been sweet to my palate.
The new version is straight to the point:
I passionately desire to sit in his shade,
And his fruit is sweet to my taste.
I doubt that alteration marks an official shift on matter however, the effect was probably unintentional. The verse format also helps to make the meaning much clearer in this book as a whole. The biggest improvements seem to be in the Old Testament generally, especially in Proverbs, Psalms and the Prophets, whereas many awkward phrases remain untouched in the New Testament. Was that because they felt more at libertly to improve the text of passages that are less doctrinally important and less frequently scrutinised?
Some verses will take some getting used to, even if they are slight improvements, Heb 10:24:
And let us consider one another so as to incite to love and fine works, not forsaking the gathering of ourselves together our meeting together, as some have the custom, but encouraging one another, and all the more so as you behold see the day drawing near.
And in the same chapter another obscure verse 35:
Do not, therefore, throw away your freeness of speech, which has a great reward to be paid it.
Is made clearer:
Therefore, do not throw away your boldness, which will be richly rewarded.
The infamous phrase, "mentally diseased" is removed from 1 Tim 6:4 and replaced with "obsessed", so I guess they won't run into trouble over that particular term any more.
I wonder if more JWs will now actually read their Bibles as the version is now almost readable.