I like the sound of this system for a couple of reasons. First, it means I don't have to try and figure out the exact price of an inn room or a mug or ale or anything--if it really is expensive for the PCs, make a check, otherwise just assume they can buy it. It seems to mean less work for me in many cases, and to make more sense than telling the 10th level PC with 50k worth of gear "you spend 1 silver on food." It also uses a built in mechanic for barganing (the random factor), so I don't have to try and play that out with the PCs if I don't want to. Also, I'm looking to run a naval campaign with the possibility of a lot of trade goods and stuff. It seems like it would be easier to say "you have +20 wealth of foodstuffs on your ship" than "You have 10,000 gold of foodstuffs on your ship," If the PCs go into pirating or trading, the profit gained could be an easy check. I'd be abstracting the wealth system, in exchange for making stuff like the combat system more definate.
But my question is, how do I convert from D&D's gp system to the wealth system? What kind of bonus would a character have at particular levels? What would be the DC of various items? Anyone have an easy conversion from gp-value to wealth DC?