Since it was first created in the 1970s, the goal of the New International Version of the Bible has been to allow Bible readers to see as much of the form and structure of the original languages as possible, while at the same time making the meaning of the Bible clear in modern English. In every verse the NIV uses the best available evangelical scholarship and the best available data on contemporary English usage to communicate God's unchanging Word as clearly as possible. Working directly from the best-attested ancient biblical manuscripts, NIV translators meet yearly to monitor changes in biblical scholarship. The latest edition of the NIV Bible represents the fruit of this constant quest for accuracy.
One area on which the translators concentrated in particular for the 2011 update to the NIV was gender language. Whenever the original languages use words that are clearly intended to communicate to men and women equally, the updated NIV uses words that will be understood that way in English, like 'humans', 'people' or 'mankind'. Whenever the original languages use words that are intended to communicate specifically male ideas, like the names of God for example, the updated NIV uses words like 'he' and 'him'.
More information can be found on the site of the translators of the NIV: www.niv-cbt.org