This is required reading before you redesign/renovate your website. You could lose all of your cherished search engine rankings for a significant time or even permanently. Here are a couple sites I've found that half already covered the topic.
Oops, I Redesigned My Website! Best Practices for a Website ... 27 Jun 2008 ... How can I make sure that I don't lose my search engine rankings? ... you'll be in a good position to manage your site redesign with care. ... reports we've read say that Google will come back again if a page fails once. ... After a redesign be sure to run a link validator on your website to be sure ... www.yourseoplan.com/website-redesign-seo/
Lost Organic rankings after website redesign - Webmaster Central Help* Lost Organic rankings after website redesign. ...* My company website completely dropped off Google rankings for our target key phrases only. ... www.google.ru/support/forum/p/Webmasters/thread?tid...hl...