Unless they plan to make major changes I fail to see why they "upgraded" to a new FF online. That barely looks better than what they can do with FFXI.
Square also have a long history of setting the standard to the weakest platform, they won't have 2 versions with major differences. They willl have the ps3 version and the pc version will be the same with higher res, that way they have one version to work on, having 2 differerent coded versions means vastly more testing times and coding time for any content they add/change after release for patches. They won't do that.