I can't say I've ever noticed any delay in sound in my PS2 or GameCube games using a Toshiba DLP. And they look amazing of course.
It could have to do with the way you set-up your home-theatre system and/or the cabling you use when you do. Off the top of my head I can't recall if my consoles have their audio directly into the receiver or if they go through the TV. I assume they go through the TV, and the connection from the TV to the Yamaha receiver is an optical cable.
