Rule of thumb: if someone takes a photo of his own monitor instead of making a screenshot, purporting to have stumbled over some unannounced product, it's fake.
I would usually agree with that, however some people always use the wrong tool for the job. Photos saved as GIFs/PNGs, logos saved as JPEGs, spreadsheets done in Word/Pages, PowerPoint/Keynote presentations saved as plain PDF files, photos of computer displays instead of screenshots, the list is endless.