Even though it has not launched in the United States (or countries other than Brazil and Australia for that matter), it does open up interesting possibilities when it comes to positively engaging your target audience. Even though it does not replace actual other ads, chances are that that over time it may do so. After all, if you had ad space available, would you select the one ad that made someone feel good about themselves and had positive feedback or would you select the one that did not inspire such goodwill?
While users cannot select who is going to see the ads that they select (meaning that it is impossible to target a particular person), the app does introduce new possibilities when it comes to personal marketing. If you can ensure that your target audience starts sharing your message amongst one another on a personal note, it not only widens the range of your message but also increases recall when it comes to your product.