Originally posted by 2K Knowledge Base:

• Continued stability and performance improvements have been made to enhance the overall experience.
  
• You now have the ability to obtain Skill Boosts directly from your in-game phone no matter where you are on the Cruise Ship.
  
• Perfect Release SFX now have descriptive names to make equipping them a more simplified process.
  
• Zoom adjustments to the Broadcast camera, based on community feedback.
  
• Addressed an issue where the user would sometimes appear over the ocean when accepting an invite to the Cruise Ship.
  
• Slightly increased the ball drop speed in MyTEAM.

Source[support.2k.com]

If there are any issues, send in a ticket to 2K Support via the usual method. Links are in the Useful Links thread.

I assume it overwrites a lot of files rather than adds new modes. They've made it clear that the 9th Gen version is not coming to PC this year.