Interesting because on my old canon dslr I had to press the depth of field button to get the view with bokeh. While looking through the viewfinder everything was always in focus, no matter what f-stop the camera was set to.
Phil should have been more specific but at the same time I still think he is right by what he said. After downloading and using the 10.1 beta with the portrait mode I understand it even more.
The iPhone camera is able to automatically adjust the f-stop or amount of blur automatically just by moving the phone closer or father away from the subject, or if you were to move around the subject totally changing what would be in the background.
It's all done continuous and automatic, and I think that's what Phil was bragging about when he said dslr cameras cannot do that. To be honest I haven't seen a dslr camera that can do it all "automatically" in live preview.
I'm not even sure if I'm explaining it clearly. But if you guys download the beta and try it you'd understand. It even tells you if you're too near or far to focus, also if there isn't enough light.