We upgraded 'inline diff', which is our module that highlights new text. 

It defaults to off, so each user will need to click on the 'highlight changes' in order to get it to function like you are used to.  Once you click it once, it will remember your preference and keep it on for you.

Unfortunately I can't default it to 'on' or I would.  

Please give us a holler if you find that it isn't functioning correctly for you.  This is a development module so any feedback we can give them, would be appreciated by the Drupal Community.