September 10, 2015 at 7:38AM, Edited September 10, 7:39AM
New GH4 Firmware 2.3 Ready to Download
This is the new GH4 firmware required to install V-log. You still have to purchase a V-log upgrade kit to enable V-log on your camera.
Panasonic Firmware Download Website
How to Install V-log on Your GH4 Camera
Panasonic Website to Order the V-Log Upgrade Kit
You can also order the V-Log upgrade kit via local camera stores when they have stock. Here in Canada Vistek expects to have this kit in stock by September 30th.
I've also heard that the GH4R camera ( that comes with V-log already installed with NO European 30 minute recording limit ) is starting to sell in Europe.