Double Page Spread Research

The give me a greater insight as to what the conventions of a double page spread are, I decided to look at a couple.

This one is a double page sread from NME:
<iframe src="http://prezi.com/embed/gwd0yuxst0a_/?bgcolor=ffffff&amp;lock_to_path=0&amp;autoplay=0&amp;autohide_ctrls=0&amp;features=undefined&amp;disabled_features=undefined" width="550" height="400" frameBorder="0"></iframe>

And this one is Kerrang!:

<iframe src="http://prezi.com/embed/_7ucvieojj-l/?bgcolor=ffffff&amp;lock_to_path=0&amp;autoplay=0&amp;autohide_ctrls=0&amp;features=undefined&amp;disabled_features=undefined" width="550" height="400" frameBorder="0"></iframe>