I used to go to some effort to make my Photoshop renderings look indistinguishable from a real photo. The third or fourth time a client mistook my proposed work for work that had already been completed and photo'd, I stopped. I know it's completely possible to create a forgery indistinguishable from a real image; the forger merely needs to be as smart as anyone who would be trying to detect the forgery. Get the shadows and reflections right, and a good forger has already bested 95% of anyone attempting to ferret out the forgery.
So I'm pretty excited about encrypted electronic watermarking. A "hologram" is embedded in the background noise of an image, and an encryption key will detect whether the image has been tampered with. This way, news services (for example) can verify the integrity of a digital image.
I'm in the business of altering reality. I show people what is possible. I want my news to be in the business of reporting what is real, so I support digital watermarking.