We had our announcement edited and ready to go not too long after the other major sites started publishing it, and we included links from the Loncon 3 web site that tested out correctly. However, the official press release from Loncon was "embargoed" — that is, those receiving it were given a date/time before wish Loncon did not want the information released. The various news sites were publishing the information prior the embargoed date/time, probably because Loncon's own site had the nominations pages "open for business." This may have been a "soft open" by making everything available before actually announcing it. (That's what I would have done.) It may have just been a mistake by the L3 web team.
So why didn't we go with the announcement until the next after the embargo officially lifted? Because several years ago, THA.org accidentally broke a news embargo. While we were accused of having done so deliberately so we could "scoop" everyone, the real reason was technical, related to how WordPress interacted with LiveJournal. A draft, unpublished announcement on THA.org, when we saved it in draft, unpublished form, published itself to LiveJournal, and everyone who spotted it ran with it, much to the dismay and furor of that year's Hugo Administrator. Consequently, we were struck off the list of "people we can trust with the The Knowledge" for a while, and it's only been in the past couple of years that we've been grudgingly been given limited advance information.
It took us long enough to get back in the good graces of Hugo Administrators that we are very leery of breaking that trust, even when the current year's Worldcon has apparently done so. Therefore, we waited until well after the embargo lifted before publishing our own announcement. Once burned, twice shy.