This Houston, TX wall mount installation was completed today.  We wall mounted a 55in Vizio on a tilt wall mount over a fireplace.  Due to the high mantle we kept the HDTV as close to the mantle as possible and tilted it down into the living room to achieve the best possible viewing angle.  Video signal is handled via HDMI cables that we routed throught the wall.  This installation really turned out perfect with no visable wiring.