070829 & Mysterious Marketing
A quick Google search of "070829" reveals there was a lot of interest in this campaign. So I'd say it has been successful in generating buzz.
Here's one film that's generating lots of buzz by letting the fans imaginations go wild. As seen in the many blogs like Cloverfield Clues, Cloverfield News and Project Cloverfield. The guys at Paramount got this one right as everyone is doing the work for them.
If you need any more proof that this type of marketing brings out the nerds check this very nerdy Youtube analysis of everything released for Cloverfield. 350,000 views for this!? He sounds like Perez Hilton.
B!X and his site OMGWTFEHWR was the first to uncover the link between EthanHaas and AO and covers the promotion quite well.
So let that be a lesson to all you experimental marketers. If you are going to go underground and do an ARG or mysterious promotion, make sure there is some link, even if tiny, to the product or service you're actually selling or risk having it attributed to something else and all your hard work wasted.
Have you seen any other good examples of this type of marketing? Please link it up in the comments.