One thing to add to that: People are not just wildly different in their opinions but also in their demeanor. I used to develop a fairly popular app (GeeTasks),

One thing to add to that: People are not just wildly different in their opinions but also in their demeanor. I used to develop a fairly popular app (GeeTasks), and I had fans in my forums overflowing with enthusiasm for the app and hostility towards an occasional detractor. I would have assumed they were paid to do it, but then I most certainly did not, and I can scarcely imagine that my competitors would. Having witnessed this first-hand I given up on my formerly impeccable shill-detecting skills.