| Especially those that are professional, or take professional-looking photos.
This AP News article c/o Yahoo! is worth a read.
On one hand, it's nice to know that "good" work gets noticed. On the other, I do see a use for something like a virtual negative as proof of copyright ownership.
Pity that solutions like Digimarc are (now) cost-prohibitive for the casual or hobby user. Sadly, their lowest tier used to be free, and it was a cinch to apply with a Photoshop filter.
My own experience with this technology is limited to Digimarc/Photoshop and was some years ago. I'd be interested in hearing about other's current opinions/experiences. I also hope to eventually take the time to learn/use GIMP at home.
'Course implementing this properly presumes application of a standard such that the photfinishers of the world could easily adopt it. | 
