Same thing with the unibody MacBooks, to say nothing of the Air. Had a MacBook and a much less expensive PC laptop from the same generation in the house; I'm still loving the MacBook, while the PC is long forgotten.
Even bigger effect with the iPhone. That one looked impressive from the start, but it made a world of a difference to actually hold one in your hand.
The iPhone 4 had the Retina display, and so that time the nerds were actually salivating over it, because the higher resolution could finally be expressed as a number and put in a chart. Nah, just kidding, the nerds were adamant that nobody needed that many pixels anyway, and preferred to argue about the "Retina" monicker. As for myself: waited until I saw it in person, was blown away again.
I'm not going to buy an iPhone 5. My iPhone 4 is still serving me fine. But from past experience, I know that the only good way to evaluate an iPhone is to actually hold it in your hand and use it. That's why I'm more interested in the impressions of a Gruber holding an iPhone 5 than in those of a bean-counter holding an iPhone 5 data sheet.
PS: just a small concession to the specs game: are you sure "the S3 beats the pants off the iPhone 5"? If you do a google search, you'll find as many people saying the 5 beats the S3 as those who say the opposite. Geekbench scores for the S3 are all over the place (check the browser). Then there's the question of whether most apps can scale to a 4-core processor as well as Geekbench does. And then there's the fact that the iPhone 4 performed much better in practice than higher-clocked Android phones of the same era. I'm sure Android has gotten "snappier" since then, but we should have learned a few lessons by now.