i vaguely remember seeing the rockband style one you posted, but this one is much nicer. It's all metal and the ventilation should be just as good as if it was standing up on top of my cabinet.
No one was questioning the ventilation on that one, though hopefully grabbing a controller or game doesn't cause it to rock any. That will scratch games.
That's what my concern would be, or any rocking at all. If someone hit that thing with my 360 on it and it fell over and my console shattered, I'd be pissed more at myself for being the dumbass that put it on there to begin with. >.>