The Dutch website http://www.seohandleiding.nl/google-strooit-met-kruimels.html has an article on the introduction of Google breadcrumbs.

But what are the consequences of the introduction of Google breadcrumbs?

Should we now alter our website structure? Google says the change should result in more clicks to the website. I forsee one problem though! As a SEO specialist you have made sure your page matches the used keyword in Google. The page its contents match this too. This ensures a match between the content and the searched keyword. This should result in lower bounce rates and higher conversion rates. But when someone clicks on a higher level in the breadcrumb they end up at a different page. This page doesn’t match in content and keyword. How would this effect your succes rate?

So you shouldn’t only look at your website’s structure, but you have to make sure there is a continous match between the searched and the result. You could choose to display the used search keywords (e.g. “You have found our website by using ‘keyword’ on Google”.) This technique is also widly used by webshops and research shows this could improve conversion by 24%.