So many states have adopted the California rules, I'm not sure that the manufacturers actually make a different vehicles any longer for CA (and the posse behind them.) They do have different warranties, though, as part of the deal; I think that not only are the CARB rules strong, they require a certain warranty to ensure the car stays that way. Good for consumers.
We are sure to hear some wailing and gnashing of teeth. This mandate will only give the oil companies/refiners yet another excuse to raise prices. Along with the Nigerian insurgents, broken pipelines, refinery fires, shortages of additives, spring/summer blend change-overs, they'll have this low-sulfur mandate...