It means that installations now need to be hardlined into each other, and can't go 'wireless'. It's designed to make the battle flow simpler to follow, and not leave us scratching our heads.
Up until now it's been a bit of a free-for-all when it came to deciding the next target to attack which ends up splintering both offensive and defensive forces.
A short tutorial that's interactive has also been introduced to better prepare newcomers to the way PlanetSide 2 is paced, which can leave some a little jarred otherwise. Sony have also rebalanced some things and added other bits and pieces, with the full GU09 patch notes.