I agree with the sentiment below that the scrolling animation on the main images (shrinking them down and changing photos as you scroll the article) is pretty nifty.
That said, the images take up a huge amount of screen real estate when you’re actually into the article. On a small laptop or a tablet, I’d think that most users would find this negatively impacting their attention to the text content, thus impacting their comprehension.
One alternative might be to shrink the image to the width of the right side bar and still make it ‘sticky’ to the top of the browser as the user scrolls. This would still allow for the images to change while they read but get them out of the way of the primary content.
Nice subtle transformational effect in The Aesthete, where an article’s splash page shifts into a photo gallery as readers scroll down the page.