Excellent analysis on Rainer Brockerhoff’s Weblog:

One of the salient points repeated at the WWDC keynote was Leopard’s support for “64 bits top to bottom”. However, a close peek at the slide shown this year showed a subtle difference to last year’s - the word “Carbon” was missing. Of course a storm of confusion soon ensued, with the usual wailing and gnashing of teeth from some quarters and polite shrugging from others. Apple stock fell and rose again, some developers professed bliss while others threatened to leave the platform, non-developers wrote learned analyses about obscure technical points, not to speak of reports of raining frogs or even an unconfirmed Elvis sighting in a Moscone restroom. Allow me to try to explain all (well, Elvis excepted).