Team Ninja released today a list with all the changes Dead or Alive 5 will see in the upcoming patch, which hits PS3 on Jan 22nd and Xbox 360 on Jan 29th. The list is actually quite large with many, many things in both system changes and balance ones. Many issues will be addressed in the ranked matches settings like forcing people to play 3-round fights, lowering Normal health setting to 270 and fixing many bugs in almost all modes.
A new stage is being added, Zack Island which I suppose is a beach. I hope it's good because one of the weak points of the game in my opinion is the stage variety (which is supposed to be a strong point for the franchise, but the Circus and Oil Rig stages come up too much). There's also a necessary change that will allow players to unlock characters and costumes by playing ranked online matches. Too late for those of us with Alpha-152 already though.
In the balance part, all characters are getting buffs and nerfs that will definitely change the way the game is played. Helena is safer and has a new CB move from BKO, Tina got a throw from SS, Busa seems to be faster and so on. On paper, most of those look like they're going to be good but it's up for the players to put them to practice and decide for themselves.
The full list of changes can be found in these two links: