deadsea - 4:15 pm on Jan 22, 2013 (gmt 0)
Our DOMs were completely overhauled. We moved from a table based layout with lots of inline styling to a div based layout with css styling.
From an SEO standpoint, I was most worried about the position of navigation links within the source code of the page. Would it matter if they moved from the left column to the footer? We did some testing on moving the navigation on a portion of the site before the new design launched and ended up keeping the navigation in the left column.