Credit: Recode, @XBLFoxes
A curious aspect, according to Recode, is the option to "see how other users from around the world have edited the same photo." Furthermore, Twitter will supposedly "suggest photos that you can edit and post to participate in trending conversations and breaking news." That sort of description suggests the feature is built for doctoring other people's photos, rather than your own. Such an approach makes sense for so-called "viral" news -- those moments when Twitter explodes with reactionary comedy.
Stickers are still in a testing phase, so there's no guarantee that they'll ever roll-out to everyone. Nevertheless, it's an interesting peek at what Twitter's developers are working on, and an indication of how the company hopes to fight the rise of social apps like Snapchat.