First, this change is not for the upcoming season - it is for the 2013-14 season.
USAG is attempting to ease the transition to the higher optional levels. In order to do so, they decided that a "level" needed to be inserted before the current level 9 that leads into the bigger skills trained at level 9. In order to do this and stick with some form of sensical numbering system, they called the new level "8" (since it comes before "9") and consequently had to bump all prior levels down one number. Now, at the same time they were doing this they took the opportunity to restructure each level a little bit where needed. All of this with the end goal of easing the transitions to higher levels as girls go through the system.
I can tell you from watching our gym, that the current jump from 8 to 9 is HUGE, primarily on beam, bars, and vault. This new level will maybe keep girls around longer and lead to more success at the optional levels. It will take time for everyone to make the transition; it always does. But the athletes won't be the ones trying to figure it out.
Good Luck