Yep.. It's just the natural progression of an MMO..

they will keep merging servers as the game ages and the population dwindles until its no longer cost effective...

eventually it will reach the point where it's no longer viable for SE to run the game.. at that point sometimes old mmo companies give out the source code so hardcore fans can run their own servers or sell it to rmt companies who can put rmt models into the game to sell currency or items.

I still think the game has years ahead of it.. but it would be silly to think ffxi will last forever.