I have a 50" Plasma that is wall mounted using the articulated Sanus SANVMSAB, I paid $80 which I thought was fair for the features.
As a 'tweaker' - its nice to have the articulation so I can move the display away from the wall and change out cabling. ;-)
As a 'tweaker' - its nice to have the articulation so I can move the display away from the wall and change out cabling. ;-)