Zivush - 4:40 am on Aug 29, 2012 (gmt 0)
1. The site doesn't have quality links as compared to its competitors.
2. Time on site and page/visit went down since the new design and other layout changes.
3. Mass deleting not the right pages or too many pages.
4. Thickening the thin content - Sometimes thin content is what expected.
5. 301 to a new domain - It is a new site for Search Engine with all the consequences..
Sometimes 'improvement' takes the opposite direction - deteriorate.