#1 Some people have been saving up mats in speculation as to what is going to be worth a lot concerning blacksmiths and jewel crafters. The answer is a bit more complex and market impact will have a lot to do with the server professions composition on your realm. But in short.. Yes Ghost iron and living steel will take a major jump in price along with trillium and serpents eyes for jc's. This will also impact the lower level ore markets but in a more direct way then just the fact that people will not be farming those ores. In fact many people will and i will explain that in a bit.
#2 You will not be able to just jump on the island and learn these new recipies on day 1. There is a realm progression that opens up parts of the island peice at a time. As i was not there in the earlier stages of PTR i am not positive on how the whole progression is implemented or unlocks but it is fact that there will be an amount of time it takes to get the Thunder forges unlocked in order to get the quest line for the Patterns and to make the Lightning Steel ingot.