If you are plugged in to my Twitter feed you may have already seen this, as I posted this earlier today.  I found this while I was doing some competitive analysis of the SEO efforts for Toyota and Honda, among others.

Both Honda and Toyota, among others, are getting Google Sitelinks to their deep pages.  We’ve all seen Sitelinks for companies whose websites are highly relevant for a specific query.  But I have never seen Sitelinks going to a deep page before.  Not only are they Sitelinks for a deep page, but they’re Sitelink for a deep page on a subdomain!

Google Sitelinks for Civic Deep Page

I think this is a great example of why very good internal site architecture is critical to search engine optimization.  Historically, automotive manufacturer websites have been experiential sites, often using a lot of Flash not only for the imagery but for the navigation menus as well.

Honda's Flash Navigation Menu

As experienced SEOs know, these Flash navigation menus create significant crawlability issues for the search engines.  Honda is using an HTML underlayer beneith their Flash naviation that mirrors their main Flash navigation.  Not only are they using an HTML underlayer, but they have programmed it so that they layout is attractive to the user.

Honda's HTML layer underneith Flash

It is important to point out here that using an HTML layer under your Flash is completely okay in the eyes of the search engines as long as you mirror the Flash content. If you create an HTML layer under your Flash and just plug a hundred different keywords, that’s not okay. But if the HTML text is a replicaiton of your Flash content, you should be in the clear.

Honda doesn’t muddy up their HTML layer. It is just a very basic, well-laid out replicaiton of their Flash navigation. The search engines can easily crawl these links, and if users have JavaScript or Flash turned off, they can still easily get to the deep pages of the site.

By creating very clear internal site architecture that can be easily crawled by search engines, even Honda’s deep pages have been able to achieve sitelinks. I would be curious to know the click-through rate and traffic increases for users whose search returns a Sitelinks result versus results that do not include Sitelinks. So far, I have seen some reported cases of traffic increases exceeding 30%.