There is no need to transfer you just log in and there you go. All stuff is stored on the same server so if you log out standing in a field on PC you'll log in on the PS4 version right where you logged out in the field on pc and can continue playing.
There is no "transfer" needed. Every version of the game plays on the same servers, thus you have your characters no matter what. All you need to do is make sure that when you get the PS4 version, you register it to the same account that you use on the PC.
This is amazing. Thanks, guys! Quick question though. Is it still possible to grab the PS3 version, log in with the character I've been using on my PC, then do the PS3 to PS4 account transfer?
And if so, do I need the disc once I've done the transfer?