Once a rumor or leak hits the Web, it's out, period. If it's an Apple rumor, it's likely on Digg. Other Mac users, like I did, downloaded the images to their hard drives en mass, in the event the takedown notices were issued. If the photos were reposted anywhere, they're on blogs, and Google Images would be next to reindex the images in their library, and cache them forever. Archive.org may crawl the page and take a picture. Even if Apple Legal reached out to everyone, and everyone complied, those images are out for good.
It's an oft-repeated sport for the Mac rumors sites to seek out leaked info, and then for Apple Legal to go after them. But even though I respect Apple's need for secrecy and privacy and for them to break the news, in the world of the Web, with such a maniacal fan base as they have, resistance is futile, and they might as well focus more on those internally who broke the rules, instead of shooting the messengers.