This seems like a good enough place as any to post the official translation concerning new races appearing in the future of FINAL FANTASY XIV. When asked about the possibilities of adding new races, Yoshida had this to say.

Quote Originally Posted by Naoki Yoshida
Though new races are quite far off in the future, once various fixes are made, the PlayStation 3 version launches, and the timing is right for an expansion, we will be adding original races to the world of FFXIV.

First, to coincide with the PS3 launch, we will be adding female Roegadyns and other genders to those races that are currently lacking. The next step is to look into new races.
Still a ways off, but feel free to let your imagination run free!