Information has been given out about 2.1 in the form of posts from Yoshi P himself. Anyone here who doesn't browse the FF14 Reddit forums should check out these links.
2.1 Release Date 12/17/2013
Note: Completion of Extreme Mode Primals will yield a lvl 90 weapon
24m Premades not possible (?) (Unsourced)
Allagan weapons will be ilvl95, Moggle Mog will drop lvl80 weapons.
Ultima Weapon Extreme (?)
Update to positional lag, will be faster in high level content/Wolves' Den
Full Live Letter w/ translation
PvP will have ranks up to 30, dungeon experience gain increased by a factor of 1.5, more info on treasure hunt
http://forum.square-enix.com/ffxiv/t...s!-2.1-and-2.2 <- Post removed by SE
Crystal Tower/Extreme Mode Primals will be a 1 week lockout (1 loot roll per Crystal Tower lockout)
FF14 is coming to Steam!
FF14 launches on PS4 in April.
2star recipes that require more than 1125 stones will be reduced to 1125 stones.
Also of note, Allagan Stones of Mythology will be capped at 450/week post 2.1 launch.
As of now, it's uncertain whether or not the questline for the ilvl 90 weapon awarded for defeating the Ex Primals and Ex Ultima Weapon will be repeatable. It's known, however, that the "high level" accessory awarded for defeating them will be attainable once per week.