The tradeskill nodes were too dense in Deepholm and Twilight Highlands for Mining and Herbalism. Several have been removed.
And by several, they mean 75% of them, which means that Elementium Ore and the Herbalism equivalent should double or triple in price by tomorrow. If you see any stocks sitting on your server at under 100g, I'd say buy as much as you can. No longer is it feasible to level by mining/herbing. This is a good change given how many nodes there were and the reality that it had the potential to ruin the economy. It is a great short-term opportunity to profiteer, but you are probably already too late if you have a few shrewd investors on your realm.
However, they didn't touch the mining route in Uldum, which I'm going to run until there are a few other people doing it thus ruining its value. Another thing to look for: All of the Volatiles should increase in value between today and tomorrow. There just aren't nearly as many nodes out there, and supplies are going to get scarce really fast.