In Diablo 2, magic find had a fairly well known formula, with no diminishing returns for magic items, and then different curves for rare, set, and unique items (with unique-find diminishing the fastest).
After deciding on the base item type to drop, D2 would roll a chance for it to drop as unique based on the monster, your magic find, and the diminishing return formula, if that failed, it would roll again to see if it dropped as a set item, then again for rare, and finally for magic, dropping a non-magical item only if all of those checks failed.
Does Diablo 3 drop items and use diminishing returns in the same way? If so, is the formula the same, or was it tweaked?