Sorry to be "that guy", but it does say this on the very same page that says about the incentives:

From: http://na.finalfantasyxiv.com/lodest...5d22338cf55ce7

Character Creation Bonuses on Preferred Worlds

Creating a new character on a Preferred World will earn you the bonuses outlined below.

These bonuses will remain in effect until the active player population of Congested and Preferred Worlds has stabilized. Please note, however, that the population status of a World is subject to change, and that if a World is removed from the "Preferred" category, the EXP bonus will no longer be applied.
That's always been there and it says that before it even tells you what the incentives are.