Conquest and Valor will be converted down. No confirmation yet on if Justice and Honor will be kept, but most likely they'll just convert Valor and Conquest to Justice and Honor respectively up to their caps and the overflow to gold like the last two major patches.
I'd say they'll either be converted or switched to gold. I can also see blizzard removing the Conquest -> Valor switch that you can do aswell, due to them wanting to make pve and pvp seperate gameplay.