I actually wrote that post based off of some tips and hints that Square-Enix (as well as others who have seen Versus 13 behind closed doors) stated. I created the post knowing that there was a very high chance that Versus 13 would in fact be for the PS4 under the name Final Fantasy 15. The joke is, it wasn't a joke!
Now with that being said, feel free to check out the original post here, and watch the trailer as well!
http://www.nettosgameroom.com/2013/04/final-fantasy-versus-xiii-now-final.html