Eric Cote posted some early GH4 2.0 firmware testing results at Mirrorlessjourney.com. The video on top for example shows Improved performance of 1-area AF in video recording:
I ran some tests with the Panasonic 20mm f/1.7 open at f/2 to stress it. Well, I can’t say how it was before but I can say it is still far from perfect or even usable. It still hunts a lot and have some trouble following even when moving slowly. In 4K, it seems to hunt even more back and forth. I will still use manual focus with the focus peaking.
UPDATE: Seb farges tested the 4K photo mode:
GH4 North American store links:
GH4 camera at Amazon, Adorama, BHphoto, Ritz Camera and Panasonic. Price: $1,698. In Canada at Vistek.
GH4 camera with interface unit at Adorama and BHphoto. Price: $3,298
Interface unit only at Amazon, Adorama, BHphoto and Panasonic. Price: $1,998
GH4 Europen store links:
Germany: Wexcameras, Marcotec-shop.de.
UK at Wexphotographic, CameraWorld, UKdigital, CVP, TipTop.
Holland at Fotohanskeuzekamp.
Belgium at Fotokonijnenberg.
Norway at Fotovideo.
Sweden at Cyberphoto, Skandinavianphoto.
Finland at Telefoto, Topshot, Verkkoauppa.
France at Photocineshop.
Kingston 16-32-64 GB SDHC UHS-I Speed Class 3 at Amazon (Click here), Adorama (Click here) and BHphoto (Click here).
Sandisk 16-32-64 GB Extreme PRO SDXC UHS-II Memory Card at Amazon (Click here), Adorama (Click here) and BHphoto (Click here).
Transcend 64-128 GB High Speed 10 UHS-3 at Amazon (Click here) and BHphoto (Click here).
Panasonic 16-32-64 GB SDHC-UHS-I U3 Card (90MB/s) at Adorama (Click here) and BHphoto (Click here).