Here's one of my favorite stories. When the Pioneer Elite Plasma first came out years ago (When the 42 was 15k) I watched with my own eyes as the Pioneer rep, during a demo hung one of those things with 4 drywall screws and 4 washers.  I almost pissed myself. 

He only did it for demo purposes, Then he turns around and says, "I don't recommend this".  No friggin kiddin' you don't recommend it. 

He claimed that because of the design of a flat mount bracket, the TV pulls straight down so as long as your in studs your fine.

I always just figured that he left his tools at home. 

I still don't have the huevos to try it.