While Square Enix's initial FFXIV press release listed series veteran Nobuo Uematsu as the title's composer, many on the floor believed this to mean that he would be contributing a few themes to the game, similar to what was done for Final Fantasy X and XI. However, a member of the FFXIV confirmed that at this time, Uematsu is set to write the entire soundtrack. While he's not back under the Square Enix roof, this is the first time he'll score a FF soundtrack single-handedly since FFIX.
Note: Uematsu's involvement was announced in the first press release that SQEX sent out about FFXIV, but it was assumed by most he was writing a few tracks for the game. This is confirmation from a member of the team that he's in fact scoring the entire game.