A couple of co-workers and I have been going back and forth regarding a re-design of a site and how the SEO would be effected. The site really hasn't changed in about 5 years because the SEO for the site has been very good over that time period and people were concerned that a drastic change would hurt this. However the subject is up again because we now how a European site that we are about the launch. The debate going on right now is if we should test the redesign on the European site. The thinking is that if the European site (with the new design) starts to rank well within the European SERPs we can migrate the new layout and design to our US based site safely because it should hold pretty much the same SERP results that we saw in Europe. I understand the the results between the two SERPs can't be exactly the same because you have different competitors for each region, but what we are trying to avoid is a major crash in the rankings. Does anyone have any experience on this or tried this and is willing to share?