The biggest thing is that it now comes with Ableton Link.
Gabber heads will be happy too as the bpm now can reach 999!
Google Play info:
Integrated Ableton Link for beat, phase and tempo synchronization over a wireless LAN (long press PLAY, then 'Enable Ableton Link')
New FX type: Stereo Tool
New Bypass switch for the Parametric EQs
Improved VA-Beast Unison
Increased the tempo range to 20..999bpm
Reduced the memory usage of the FX Units
Improved Latency Compensation
The OpenSL Audio System is no longer experimental
Many minor bug fixes and improvements
Full release notes at http://www.planet-h.com/g-stomper-studio/gst-whats-new/