Safari Top Sites Preview

Question

In the Top Sites section of Safari, the iCloud.com image shows the logo instead of the login screen as you can see below. Normally, the Top Sites just shows a picture of the loa

Answer 1

I believe they programmatically grab a snapshot of the page when it's finished loading. And if you look at the progress bar at the top, when iCloud shows that (just the iCloud logo), it's finished loading and is doing a little animation.