Early GH4 firmware update shows V-Log too.

GH4 Beta Firmware Sneek Peak from Matthew Allard ACS on Vimeo.

There may be also a new feature not mentioned in the official Panasonic GH4 firmware announcement coming in December: V-Log! Newsshooter asked Panasonic about that feature:

I spoke to a Panasonic representative who told me that the V-Log Picture Profile was only being tested at the moment and isn’t confirmed for the next firmware release. Interestingly enough though I did run into a Japanese shooter who had V-Log operational on his GH4.