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That was my thought process as well. Thanks Alan!

I totally agree with the notion that User Experience dictates keeping it in a regular site template. And an html page devoted to being a sitemap is supposed to be for users, not search engines.  The days of having one page with nothing but links should be over in everyone's mind anyhow.  If all a page does is provide links, with no content around them, the SEO value of all those links is minor now. Then we can talk about how much value those sitemap on-page links have anyhow -  if you've got fifty or five hundred links on that page, they're not passing very much value for SEO, regardless of whether there's top navigation, or anything else on the page.

Whether you include the sub-nav in the site-wide navigation as drop-downs or not, make sure that you also have that sub-nav as on-page links (such as in a side-bar) specific to each section.  So that only that sections page links will then be on all of the pages just within that section, without the drop-down needing to be used. This ensures proper attribution and relationship queues for SEO. Having said that, this issue is widely debated in the industry.  I've seen arguments on both sides claiming they have proof that one or the other of your choices was better.  Personally, I've always taken the approach that SEO should always be balanced with usability.  So when this question comes up I don't tell clients to kill the site-wide drop-downs.  Instead, I focus on other refinement (like the section by section dedicated side-bar links, and proper breadcrumbs, and in-content links, and so forth).  And that has always gotten my clients solid results.

Thanks for the follow up. I do remember reading about page rank sculpting and that change. Good stuff! I appreciate the replies Adam.