"About (Late 2013) Mac Pro EFI Firmware Update 2.0 (5 MB)
Mac Pro EFI Firmware Update v2.0
This update is recommended for all Mac Pro (Late 2013) models.
This update improves system reliability during reboot, resolves an issue with memory self-test, and improves graphics power management when using Boot Camp.

System Requirements:
- OS X 10.9 or later
- EFI requirement:
- EFI 0116 (MP61.88Z.0116.B00.1311020956)
- EFI 0116.02 (MP61.88Z.0116.B02.1311222014)
- Model requirement: MacPro6,1"

FYI: There's now a Late 2013 Mac Pro specific OS X 10.9.1 updater download, using the URL (DL1707) of the original (generic) OS X 10.9.1 updater D/L page from Dec 16th, which has now been changed to a different D/L page URL (DL1715). (I've updated the Dec 16th news to include all 3 updaters (generic, Late 2013 Mac Pro, Late 2013 Retina Macbook Pro) with their current URLs.)
  

"VPN Update for Mavericks Server (3.0.1)
This update fixes an issue that could prevent L2TP VPN connections from working with OS X Server, as described in Apple article (OS X Server (Mavericks) Clients cannot connect to VPN service using L2TP.)

This update requires OS X Mavericks 10.9.1 and Server 3.0.1.
Note: the update will only install if you have already launched Server app and used it to set up services." (emphasis mine)

• Optimized playback and rendering using dual GPUs in the new Mac Pro
• FxPlug 3 with custom plug-in interfaces and dual-GPU support
• Faster project loading, especially for complex projects
• Share directly to YouTube at 4K resolution
• Spanish language localization

See below for updates to Logic Pro X, Mainstage and Logic Pro Remote.
  

• Apple Compressor 4.1
• Apple MainStage 3.0.2
• Apple Logic Pro X 10.0.5
• Logic Remote 1.0.3 (compatible with MainStage v3.0.2)
• OS X Mavericks 10.9.1 Update for Late 2013 Mac Pro
• Apple's Acquisitions Tripled in fiscal 2013
• Apple Says Demand For New Mac Pro Already Exceeds Supply

The new late 2013 Mac Pros at the online Apple store were showing "Available to ship by Dec 30th" for base/standard configurations as of 7AM EST launch day (Dec 19th), but when I checked again 2 hours later they were showing "February". (They have an option to check for stock in stores by area/zip code, but all here showed only ship to store option.)
  

• About the VPN Update for OS X Server
• OS X Server (Mavericks): Clients cant connect to VPN service using L2TP (see above)
  
  
• Final Cut Pro release notes
• Resolve an issue in Final Cut Pro
• About Final Cut Pro
  - was titled "Final Cut Pro X: Frequently Asked Questions".
• Final Cut Pro X, Motion 5, Compressor 4: Graphics card compatibility
• Final Cut Pro X 10.1: How to back up important FCP X 10.0.x files before updating
• Final Cut Pro X 10.1: Macs capable of viewing 4K resolution via HDMI (no longer online)
• How to remove and reinstall Final Cut Pro
• Final Cut Pro X 10.1: Updating and working with libraries FAQ (no longer online)
• Final Cut Pro X 10.1, Compressor 4.1: Adding a "Apple Devices 60fps" destination
  (no longer online)
• Final Cut Pro X 10.1: Adding a destination to Share 4K to YouTube (no longer online)
• Final Cut Pro X, Motion 5, Compressor 4: User guides
• Final Cut Pro X: Apple ProRes White Paper (no longer online)
• Import REDCODE RAW files into Final Cut Pro
• Final Cut Pro X for Final Cut Pro 7 Editors white paper (no longer online)
  
  
• About the Final Cut Pro trial
• Apple ProRes and ProRes RAW Authorized Products
  
  
• Motion release notes
• About the security content of Motion 5.1
  
  
• Compressor Release notes
• About the transition to Compressor 4.1 white paper
• Compressor 4.1: Enabling additional Compressor instances (no longer online)
  
  
• MainStage Release notes
• If MainStage isn't working
• MainStage 3.0.2: Patch tempo setting no longer resets the Concert tempo
  
  
• Logic Pro Release notes
• Logic Remote Release notes
• Logic Pro X: Unexpected behavior with Audio Units plug-ins
  
  
• Using a USB drive with an AirPort base station
• Update the firmware on your AirPort base station
  
  
• Set advanced network settings in iOS Setup Assistant
  
  
• iOS update and restore errors
• If you see an error when you update or restore your iPhone, iPad, or iPod
• If you can't back up your iOS or iPadOS device to a computer or restore it from a backup
  
  
• How to identify iMac models
  
  
• Activity Monitor User Guide
  
  
• iCloud: My Photo Stream and iCloud Photo Sharing limits
• Use iCloud calendar subscriptions
  
  
• See or cancel pre-orders for apps, movies, music, or books
• Back up and restore your iTunes library on your PC
  - originally titled "iTunes for Mac: Moving your iTunes Media folder".