SE would be stupid to release the PS3 version when the games "Core areas" have not been completed yet, and probably a few months after they find it to be deemed "Worthy of release"
Not releasing the PS3 version as a form of expansion is dooming them to loose out on a large portion of potential customers...why is that? What will people see when they hear FFXIV is releasing on the PS3? Lets roll through some of the possible situations a consumer may think of.
1.Finally gonna get get this game right now! been following the updates and it looks/sounds like it's ready for purchase
2.WTF there is a FFXIV I didn't hear about this.
3.Sounds cool, lets see how the PC version of it fared in review....WTF! Why would I buy a port of a 4.0 game!
SE needs to draw massive ammounts of media attention with the PS3 release or risk being passed by with lack of attention and the brutal release reviews lingering on the release. SE would be signing the games death warant if they didn't release the PS3 version as a expansion pack.
Will they charge PC users for the expansion pack is another question. It would be a good form of "thanks for sticking with us while we worked shit out guys" if they let us upgrade to the new version for free.