If you are using third party apps like Litchi and you upgrade, you will start to lose functionality. The first thing you gain is a height restriction of 500 meters. You also lose the ability to rollback, and DJI Go will update itself and the RC without asking.
If you have already been using DJI Go, you will not notice the altitude restriction, because DJI added that to it's own app long ago. They did not take away the functionality in the firmware until now, meaning that all the third party apps lost their ability to let you fly above the 500m mark.
You also lose your ability to go back to an earlier version of ANY app, because DJI made changes in the coding which makes all apps developed before this firmware release inoperable. Actually, this started with their new SDK release this past October.
So be VERY sure you want to accept the altitude restriction, the loss of ability to roll back the firmware, the loss of ability to use an older app, and I am sure, more and more restrictions are coming with each new release, as DJI works hard to craft their product in a way that no person anywhere can possibly fly it and break a regulation by creating one-size-fits-all solutions designed to keep the most careless and clueless pilots from doing anything stupid at the expense of everyone else's functionality and ability to take interesting flights within regulations like flying up the side of a mountain and over it's top even if that mountain is over 500m high. Can't do that now with the new firmware. The no fly zones are next, after that, who knows?