This is actually just wrong. Compare them side by side and you'll see that the web view components in the iPhone app have been specially designed and constructed for the app.
If I hadn't had it explicitly pointed out to me that the app is a bunch of web views, I would have thought it was a ton of Core Text drawing going on behind the scenes.
See http://www.quora.com/Why-is-most-of-Quora-for-iPhone-a-wrapp...