Could mean numerous things. Nobuo Uematsu (Pretty much every Final Fantasy game, among other games, bar the FF13 series) was listed as a composer but he only wrote Brawl main theme. (incidentally, XIII's composer is on the new list)
Also I find it odd that there's no Shogo Sakai or Koji Kondo on the list...then again their contributions might be original tracks, taken directly from the game, as opposed to arrangements (ex. Forest from Kirby and the Amazing Mirror was taken directly from the GBA game into Brawl), or their contributions are on the WiiU version.
It pains me to see Yusuke Takahama on the list...he butchered arrangements in Brawl.
Also Yoko Shimomura's appearance has sparked my curiosity. He's probably my favorite out of all those currently on that list.