The division is called "command" but that is kind of misleading. It seems to be centered on helm and weapons functions, and has people who are a long way from actually taking command (Wesley Crusher). This was addressed in the TOS movies, where pretty much only the captain, first officer and admirals wore white.
One thing seems pretty sure, the lines between the TOS and TNG division colors are fairly loose. They don't indicate who can take command; Scotty and Data were not "command division" but were fully qualified to take the center seat. Likewise they don't seem to indicate a "career track": Sulu started out in sciences but rose to captain a ship, Troi was science/medical but qualified as officer of the watch.