Yoshi-P, in-game information (he logged on Ifrit server this past weekend):

- Phase 4 will be 1 week only.
- Arcanist will be available at phase 4
- Voice acting will be available at phase 4
- There will be some kind of exp bonus for secondary class after completion of first 50 class/job.
- HQ crafting from NQ materials will have adjustment.

Source: http://metenyo.blog15.fc2.com/blog-entry-8557.html

Other stuff I've also read elsewhere:

- Housing system will be available at phase 4.
- Early Access should start shortly after Phase 4 and it will be closed for those who pre-ordered the game only. Early Access is supposed to last about a week from what they said during the E3 Live Letter.
- A new benchmarking software will be available on August 1st, and it will come with a Character Creation tool. Data from characters created on this benchmarking can be imported into the actual game.
- The final version of the Lodestone is planned to have a database with all items and skills available, including tips on how to get them.