I think that it's fake cause:
1. Bonnie already told MTV that the next single has been chosen and that it is "colorful."
2. Knowing Capitol and their thirst for hits, they wouldn't do it knowing that Roar is yet to smash and be a hit.
3. If such campaign is going to be launched before the VMAs, shouldn't Pepsi, various media sites and Katy's team already announce this so that everyone will be completely informed especially that there are 6 days left 'til the VMAs?
4. Again, the fact that Roar is yet to smash and the video's not even out yet and will even possibly premiere around September 17

are just one of the many facts that that article is fake.