I personally wouldn't buy a high end computer from Best Buy anyways.
Me neither, but then again I'd rather build mine. But for someone who isn't very knowledgeable about computers, or someone who will run mostly older applications, or even someone who will just flat out rarely use their PC at all, it is very appealing.
I'm quite impressed that 17' LCDs are that cheap now, I remember when they were $1000 US each