Let me up the ante so to speak: I would say that if an educated Greek or Roman from between 300 B.C. (Periclean Athens) to 250 A.D. (Marcus Aurelius) were to show up in 2015, they would spend about a week tripping on the gadgetry (and pissing themselves --literally, in fear -- the first time they rode in a car), but then they would probably think -- oh, yeah, there are a few changes, but nothing big. Except for the steam engine, fertilizer (finally, enough food), and birth control, maybe, but only for their social implications.
The social/ cultural changes are what matters, I think, and the technology is actually much less important.
On the other hand, I think if you brought an Afghani tribesmen from the 1950s into modern US, they would be more blown away and have a harder time adjusting, (EDIT: even though they would be more familiar than an ancient Greek or Roman with telephones, cars, etc).