No CSS hacks have been used in this layout. A mixture of floats and relative positioning is all that's required for the structural divs. This method works for all common browsers.
No JavaScript
JavaScript is not necessary to make this layout work on the iPad or any other browser. The switch between portrait and landscape layouts is done with pure CSS.
No Images
This layout does not require images. Many CSS website designs need images to color in the column backgrounds but that is not necessary with this design.