I found this:
http://www.webinformers.com/google.cfm

Google is a search engine that maintains its own spider-based index. Google also has a directory that is powered by the Open Directory; however, the sites within the directory are ranked according to Google's link popularity technology.

Google spiders the web to maintain its index, with emphasis on content and link popularity. One factor that determines your rank on Google is the number of links that point to your site, the quality (popularity) of the sites that link to your site, the text in and around the links that point to your site, and who you link to.

Google's web crawler only views the visible text on your page. The meta description and keywords have little influence on Google's rankings. Google has become aggressive when it comes to elimination of spam. To be listed in Google's directory, you should submit your site to the Open Directory.

Google: "Basically, Google's position is that we prefer no hidden links, no hidden text, no automatic tools used for positioning, and no cloaking.

We prefer that Googlebot get the exact same page that users see. In general, you can assume that we're as conservative as possible. We don't like hidden links/text in divs/layers/iframes/css, or links that are inconspicuous or punctuation, for example. Similarly, we don't like cloaking or sneaky redirects in any form, whether it be user agent/ip-based, or redirects through JavaScript, meta refreshes, 301/302's, or 100% frames."

I wonder if the nexus interface inhibits Google in any way. Perhaps not since Nexus isn't the only way to view the zone.

Submission Times - Upon submitting to Google, it can take up to 3-6 weeks for your site to be listed in the index. Google will respider every page in its database approximately once every 3-6 weeks and usually publishes a major update to its index during the last week of each month.

Once every 3 to 6 weeks leaves a lot of holes in the zone. Especially if Google only looks at the front page. I wonder if another search engine would spider the pages more often and therefore be better for HZ searches. Worth doing a bit of research on.

-Steve G.