This site compares the GFS to FV3-GFS. EMC's FV3-GFS parallel plotted on this page currently uses the same initial conditions as the GFS. As development of the FV3-GFS continues, the two systems will diverge. Changes in the FV3-GFS system will be documented here.
Starting with the 00Z 19 December cycle, the FV3-GFS uses GFDL microphysics instead of the Zhao-Carr microphysics in the GFS.
A plume comparison page for the FV3-GFS can be found here
. EMC is also maintaining a VLab
page with FV3 documentation and a forum for posting about the FV3-GFS's performance.