With no new content coming after these last few updates coming, we will see a decline that is inevitable, and to say otherwise is just ignorance. The game will decline because the PS2 puts a limitation on content, and it is because of that limitation that it should be eliminated. Or as someone mentioned, let 2 versions come out:
First Version: PS2 whcih allows for small updates and the final "expansion" is Abyssea
Second Version: Xbox 360 and PC which allows for new expansions and content.