mostly taken for blacksmith or engineering

but you can also take it to make money on AH, at higher lvl when you can mine in the outlands you will get molt of air, water ... what can be sold on AH for "lots" of money cause their needed in lots of proffs.

You'll mine alot of Mote of Earth, which is not worth alot on the AH anymore since miners mine too much of it =p

But the ores still sell good, and if combinated with jewelcrafting, you could get gems from the ores and cut those into gem sockets