Download the video to appreciate the quality. The lens they’re using on the Canon 5D Mark II is no slouch… it’s the 50mm EF f/1.4 – a very nice lens so the video quality of the iPhone 4S is even that much more impressive.
Canon 5D Mark II vs iPhone 4S 1080p Video
Nice… check this out to see how the iPhone 4S 1080p video compares to a high end dSLR. It’s not the same obviously but the conclusion is that it gives consumer end dSLR a run for the money!