With, critically, one important difference: it now has two cellular antennas. This way if one loses signal, say, due to being accidentally bridged, the phone switches to the other. This is why the gaps in the metal band are different between the 4 and the 4S. (Compare them.)
It's also why Consumer Reports endorsed the 4S but not the 4. Because it doesn't have the problem. Because they fixed it.
It is useless to argue with nirvana. He is like a conspiracy theorist. He made up his mind that the iPhone 4 and 4S have the same antenna design and would rather declare PC World and Consumer Reports and you anti-Apple liars rather than admit he was wrong. This is precisely how RDF works, the story that it's Apple against the world and thus anything bad said about Apple is never true and is said only by haters.
It's also why Consumer Reports endorsed the 4S but not the 4. Because it doesn't have the problem. Because they fixed it.
See http://www.pcworld.com/article/241186/new_iphone_4s_antenna_...