I'm fairly DIY competent and although I have lived in a brick built home for 4 years and have now moved to a timber framed house I have a good idea of the things I need to do for fixing things to these kind of walls.
I have a 19" LCD that I have (already) fixed to the wall. Using a stud detector on the wall that I have fixed it to gave no results, it either detected everywhere on the wall or nothing at all. At one point I was convinced that I had found a stud, marked accordingly and drilled pilot holes. There was very little resistance as though I had drilled into a hollow wall. I decided to see if attaching the bracket gave any good results. (Did I say I was competent :) ) I was surprised that the screws bit, and that my torque driver locked. I assumed that as this wall is a connecting wall between properties that it is a "solid" wall. My question is two fold, what is the wall that I have drilled into and is the TV installation safe, before mounting the TV I pulled with all my weight on the bracket and it did not move at all.