Just 24 hours before the launch of "trucks", Fallon's follow-up to "gorilla", if you had typed "Cadbury's Dairy Milk trucks" into Google you would have found an outdated eBay archive for a set of 50s toy trucks, two preview articles and a spurious selection of broken links.
However, following the unveiling of the ad, all that has changed. Those keywords now unlock a myriad of videos, archived articles, blogs and reader responses. If the fortunes of "gorilla" are anything to go by, it will later be populated with user-generated content including spoofs, re-edited mashups, parodies, debates and social networking groups.
It is partly for this reason that Fallon has been desperately trying to cloak the ad in secrecy, hoping not only to catch the audience off guard, but, in the words of the Fallon partner Chris Willingham, set the conditions for interest in the ad to "set fire online".
But in the digital age, the big reveal strategy is not always the best promotional option. Take Fallon's other highly anticipated ad for Sony, "foam city", as a contrast.
Since it was shot in Miami last month, speculation on the ad has been bubbling away in cyberland. Unsolicited and solicited footage of the shoot (Sony went so far as to plant bloggers on the set with cameras to make sure they got just the right shots) has been uploaded on YouTube and has triggered rampant online discussion.
All of this has set the publicity ball rolling weeks ahead of the ad's official airdate.
How times have changed. A few years ago, the idea of footage leaking ahead of the airdate would have given marketers and their agencies the jitters. Willingham recalls the filming of "balls" in San Francisco three years ago, where interest in the shoot already had parts of the city talking and filming on their phone cameras.
"It was still the early days of YouTube, and there was an initial anxiety that all our rushes were going to be online within 24 hours," he says. "But we realised that there was nothing we could do."
It proved to be a blessing in disguise. The response was overwhelming, generating free publicity of the ad months ahead of the launch, tapping into a loyal group of supporters. It also set a new precedent for pre-launch publicity for the next ads for Sony Bravia, "paint" and "Play-Doh", which both used a proactive approach to get the public and blogging community involved right from the start.
Building anticipation online ahead of the launch date shows yet again how the digital age has changed the traditional rules of marketing.
The recent growth of video-sharing sites and faster and more widely available broadband connections has helped the cause, but you can trace the first signs of teaser campaigns back as far as 1999, when the low-budget independent film The Blair Witch Project sprang to fame after a groundbreaking digital campaign appeared on the internet months ahead of the official launch.
Will Collin, a partner at Naked, says that advertising is following a road that the film world has had to lead on: "Nowadays, you're never going to keep a lid on something completely, and Hollywood studios have tussled with exactly the same issue: rather than resisting, how do you take ownership and advantage of an audience who is already predisposed to your work?"
The answer, it seems, comes by feeding audience interest as early on as will be appropriate to generate interest. "If you're lucky enough to have any pre-launch interest in your brand, you should capitalise on it by giving your audience access to assets that they can share, change and propagate," Collin says. "Then it's essential to fuel the continuation of interest by releasing more information over time."
This concept of online seeding is the latest digital shift since companies discovered microsites as a means to push short-term objectives and separate a campaign message from larger, more unwieldy corporate website messages.
However, they have their drawbacks. While microsites are still popularly used, they can perform poorly in search and still carry much of the stigma of a corporate brand message that content "unofficially" residing in blogs and on YouTube simply has less connection to.
"There is no bigger wasted opportunity for marketers than trying to push a campaign message with a Flash site that Google can't find and a URL that no-one remembers," Katy Howell, the managing director of the digital PR agency Immediate Future, says. "With social media, the references are found in the essence of what people are talking about."
It is a point validated by Darren Cox, the incoming head of digital for Nissan. He recalls last year's pre-launch campaign for Nissan Qashqai, in which five virals were seeded on around 2,000 sites and also housed on one official microsite. The virals were viewed 1.7 million times on the official website, compared with 15 million views from seeded websites. Cox says: "We realised there was no point getting preoccupied with building a website to house content if it's strong enough to exist in its own right."
The latest "urbanproof" campaign for Qashqai plans to rectify this. The ad, which has been directed by Danny Kleinman, has a specially tailored digital strategy that will bypass a microsite and instead partner with video-sharing sites, seed content on a pre-selected range of blogs and content-sharing sites and release further assets of the ad, including a pre-launch teaser campaign followed by a "making of" video.
Cox explains: "The digital strategy isn't just about targeting car influencers, but also cultural influencers. Kleinman is a famous director with his own fan base, and seeding in this way allows us to widen the net in a way that's measurable and can be adapted hour-by-hour in line with the numbers."
There are, of course, a number of warnings. First, choose your launch audience carefully. You can't just put something out and expect users to pick it up and use it without an incentive. "Social media is about conversation and dialogue with key influencers in the digital space and then presenting information to each of their specific interests," Howell says.
Second, be aware of countless examples of brands whose efforts to embrace the digital space have backfired. "One of the risks of using online networks to generate interest beyond media exposure is that you risk being seen as manipulative," Collin says.
Brands that have fallen foul in the past include Cillit Bang, which, a few years ago, was found posting bogus messages on bloggers' sites, and General Motors, which, in 2006, invited people to create online ads for a new sports utility vehicle, only to find itself attacked by bloggers over its safety record and environmental abuses.
Third, unlike the broadcast period of a traditional commercial, content remains on the internet forever and a surge of negative publicity cannot be removed.
However, this is not open season for any advertiser looking for free pre-launch publicity.
"Only a handful of brands have truly earned the right to build expectation around their advertising content," Andrew Stephens, the chief executive of Goodstuff, says.
Finally, online seeding can only really work if your content is good enough in the first place. While brands such as Nike, Sony, Cadbury and Pot Noodle appear to have a rich enough creative heritage to do this, many brands have simply fallen short of the mark.
"However rough the assets and eager the online chatter, people still expect the finished film to be superlative," Collin says.