If you think just changing colors means something, then you obviously have never tried to control a fight. When you are trying to keep an opponent below one or two bars of power while fighting and looking at timers/buffs/debuffs and thinking about half a dozen different nodes, you need to see EXACTLY where that power level is out of the corner of your eye. Period.
That
That The power bar's look was updated, yet mine remained the same, probably because I have an android.