I'm not in Beta, so I only have information from Wowhead, MMO-Champion, and the related forums as a guide but...

It seems to me that either Herbing or Mining plus a crafting profession that uses the same will be the best money-maker in Legion. Getting to mine x5, x10, x15, or x20 for each node you find seems much more efficient than double crafting, and may even overtake some sort of open-world activity for gold making.

Anyone else have thoughts?