Originally Posted by Hitch
In fact, Apple specifically calls for usage of CSS3 in its iBookstore Asset Guide, as of the June 1 edition (and previous, at least through the beginning of the year), in lieu of the ADE xpgt. FWIW. There is nothing that Apple will not ignore if it suits it to do so.
Apple has also adopted HTML5 as their standard so it is not too surprising that they want CSS3.