Samsung can also point to the LG Prada which was publicly announced three weeks before the iPhone and on sale months before the iPhone. http://en.wikipedia.org/wiki/LG_Prada
Firstly, it isn't about prior art so not sure why you are bringing up an LG device. Secondly, nobody is going to mistake an iPhone for an LG Prada. Nobody. But a lot of people are going to mistake an iPhone and a Samsung Galaxy S.
Unlike with the trademarks Apple does not need to demonstrate brand confusion. With Design Patents they need to demonstrate is that a Galaxy S is "substantially similar to the design" of an iPhone. "The copy does not have to be exact for the patent to be infringed. It only has to be substantially similar."
I do not think that is significant reason to allow their product. If I make, say, a Louis Vuitton clone, but added some part that shouted 'FAKE; NOT THE REAL THING' that every buyer could remove, there still would be a case to make for forbidding the non-clone.
Apple has evidence from Samsung that plenty of people accidentally purchased (and then returned) the Galaxy Tab thinking it was the iPad. So no reason the same wouldn't happen for the Galaxy S.
Without some numbers behind those statements they are pretty meaningless. People buy the wrong product all the time and take it back. This is especially true of those people that don't understand what it is they are buying in the first place.
Samsung is trotting out it's 2006 work to show they didn't willfully infringe if Apples patents are valid. I bring up the Prada but because it shows that Apples design patent is of questionable validity to begin with.