Twitter, in its S-1 financial document filed yesterday, pitches the opportunity for “earned media and viral global reach” as one of its “value propositions” offered to advertisers.

twitterIt notes that a “promoted Tweet” can spread through the four corners of the globe due to user retweets, replies to or conversations started about. It urges advertisers to create compelling ad and then sit back while those messages are transmitted across the microblogging service’s global platform at no incremental cost.

Twitter cites the success of Mondelez International’s campaign on behalf on Wheat Thins. The $35B Kraft Foods’ spin-off piggy-backed a Twitter push onto an advertising campaign for Wheat Thins. Using the “Must Have. Wheat Thins” ad slogan, Twitter users could win free boxes of the crackers by tweeting how their Wheat Thins were eaten or stolen by fans of the product. The effort registered more than 242K Tweets mentioning the brand, which bolstering Wheat Twins followers on Twitter.

Alas, PR may also do Twitter in. From the S-1:

“We receive a high degree of media coverage around the around the world. Negative publicity about our company, including about our product quality and reliability, changes to our products and services, privacy and security practices, litigation, regulatory activity, the actions of our users or user experience with our products and services, even if inaccurate, could adversely affect our reputation and the confidence in and the use of our products and services.”

Twitter notes that service outages result in widespread media reports. That negative fall-out could affect the “engagement and loyalty of our user base and result in decreased revenue.”

Good luck to Twitter on its IPO.