Detailed Sitemaps & Partial Sitemaps in Footer back in fashion?

A co-worker recently attended a conference and noted that several speakers talked about the importance of sitemaps to SEO. He also said that a few of these speakers also recommended "fat footers" that contain a partial site map at the bottom of each page.

I just received this same advice from Whitney Hess via Twitter who was relaying advice from Smart Experience's Web Navigation Design presented by James Kalbach:

Site map: laundry list of every single page on the site organized by section. Seem to be coming back into fashion. Good for SEO Partial site map at bottom of every page becoming popular. More contextual navigation

Whitney is sharing other great advice on navigation design via hashtags.