How high to wall mount your TV?
With the correct tools and know-how a TV may be wall mounted at exactly the height that you want it; regardless of the stud pattern.
However, studs, of course may dramatically effect the difficulty of having a TV at certain heights. Generally, (on a standard plaster board and timber wall) the bottom of the TV should sit 4 to 5 inches below the middle noggin (the middle of the wall). This enables to hide the entry/exit hole for concealing cables.
What height for which size TV?
The larger your TV is, the higher you can get away with wall mounting it and having it still look good. At the end of the day however, it does come down to personal preference. Some people have reclining lounges and may want it a few inches higher. Others want it nice and low. If you have a TV cabinet we suggest that you will probably want to wall mount it a minimum of 6 inches above the cabinet (no matter how tall your cabinet is) in order to have it appear that it is indeed wall mounted and the cables are concealed. If you have a super low-line TV cabinet however, you will probably want a minimum of 24-36 inches (still aiming to have the bottom of the TV 4-5 inches below the middle noggin).
If you are using a tilt bracket..
Tilt brackets will assist you to put your TV at a higher height. This will allow you to tilt the TV downward slightly.
Kitchen TV's, Bedroom TV's
If your TV has no connected equipment at all (just power point and TV point) you can get away with wall mounting your TV much higher. As you do not have to worry about the middle noggin so much.