That's because they were done by the same people, take a look at their 'portfolio' on Dribbble - it's really impressive: http://dribbble.com/softfacade

Side note to HNers, if you're in need of great design then I'd recommend perusing Dribbble. I've found a few freelancers there that have done some amazing work.

Full size can be seen here: http://www.flickr.com/photos/softfacade/5244241757