I was asked recently if I ever create double page layouts. The answer is...yes, but obviously not as often as my single layouts. However on occasion I do have a group of photos that I feel the need to scrapbook as a series. That is when I create double layouts.
Sometimes when you have a series of photos, you are able to crop/print some of them much smaller to make a grouping like I did in this layout.
Or this one I matted most of the photos all together, making it look virtually seamless.
Sometimes you have one photo that you want to stand out. In this layout I put it on the left hand page, then I made somewhat of a collage on the right hand page.
All in all, when I create a double page layout I try to keep a continuous theme from page to page. That way your eye is drawn across your layout and seeing it as one larger layout. Rather than being broken up into pages.