Dust is basically ground battles that will exist in the EVE universe (no pun intended). You are a mercenary hired by Corporations, factions, etc from EVE. I'll give you a good example:
I work for the Edgegamers Corporation on EVE. I can make a mercenary on Dust that will work with the eGO corp planetside, and they will provide me with ISK for my services. This includes weapons, vehicles, armor, etc.
If done well, you could make money off of Dust (if you don't die, or lose ISK). But who knows.