I can only think of the poor test subjects who participated in the research for this.
Doctor: “Subject #XG-412, please swallow this tablet whole. And try not adjust the focus.”
Test subject: “Can I have the placebo, puh-leeze!?”
How about the technician who gets to collect and refurbish cameras after their short, happy trip? Not to mention the twisted technology that my follow… EnemaCam™
Nooooooo, I don’t think you really do want the placebo in this case–given that the comparison group must have been people having their innards looked at using more, erm…traditional procedures.
I for one really hope they work the kinks out of those little cameras before I reach the age where regular colon exams are a good idea.
Since the image is transmitted remotely I suspect that the placebo group was given a suger pill and just assumed that their inards were being broadcast on a big screen somewhere.
However, because the image is being transmitted from within, wouldn’t you experience some radiation effects from the signal?
Anyway, I don’t think that I want pictures of my colon to be picked up accidentally by NASA scientists in the middle of landing a robot on Mars. 
The camera is disposable, it says. So they don’t have to collect and refurbish them. Seems “wasteful” if you ask me . . .
I don’t know, Spyderman, maybe they needed that sort of placebo group for some reason, too, but wouldn’t the more important comparison be to see if the camera provides as much information as more invasive procedures?
Possibly people had to serve as their own controls in this case. Double the fun.