What is the new Google SERP highlighting?

[GeorgiaSEOServices]

My question is with the new Google SERP.  I posted a pic of it at http://www.hortonwebdesign.com/images/new-google-page.gif.

If you mouse over the arrows to the right of a result on the SERP, it pops up a preview of the page. On some results it also highlights a section of the page with a red box. What does this represent? Does it represent a key area that they are looking at in determining the positioning?

I have some clients that are asking me and it doesn't make a lot of sense. In my example above I searched for "seo expert in georgia" and on my result (I'm #2), it shows a preview, but the part it has chosen to highlight with a red box is just, um, ...useless. It's highlighting a Recent Post sidebar on the right halfway down the page. Surely this can't be what they're looking at as what they view as "useful" to that search.  This simply can't be what they're using to determine positioning. Or is it?

Just please explain what I'm seeing here.

new-google-page.gif.

[GeorgiaSEOServices]

Hmm. Let me research, but that seems like a legitimate reasoning. The only crux of that answer is that why would a typical searcher (someone like my parents) give a poo about what Google has selected as relevant? Especially when in some cases it's as innocuous as ALT text behind an image? If it wanted to utilize that feature to show the searcher where on the page was the most relevant to what they searched for, so that maybe they would know where to look when they arrived on the page, it's doing a very poor job. I think we're viewing a feature that doesn't have the quirks worked out yet because there doesn't seem to be rhyme or reason.

[SL_SEM]

From what I can tell they are grabbing the smallest chunk of the page that contains the highest proportional use of the keyword. In some cases they can't get it all in one spot so the pull two separate highlights (check out hostgators preview on a "dedicated servers" search).

So a lot of the examples I see are a tagline or header that has the term. When it is a less naturally used phrase like "SEO expert in Georgia" then it will probably pull results like you are seeing. If you put a sentence closer to the top of the page that said something like "Your #1 SEO Expert in Georgia" with a sentence below it like "SEO experts in Georgia can be hard to find" I bet it would pull that out instead.

[GeorgiaSEOServices]

That's what I had originally thought.  But that's not all there is to this.  Even in your example for Hivelocity.net, it's showing the searcher (assumed) what it found on the page that was relevant to what they searched for.  But by that logic, is it then saying that the text behind the image is more relevant to "dedicated servers" than anything else it could find in its database? This is where that assumption kind of falls apart. Especially since the area they're highlighting wouldn't even be visible to a typical user that never has even clicked to see source code before.  The selections seem haphazard.

It's almost as if they're giving us insight into the algorithm and what it sees, but the value of what they're showing is bottom of the barrel. Even when "Dedicated servers" is in their title tag, header tags, etc., but it chose text behind an image?  There's more to this...

[SL_SEM]

The highlight is showing you where they found content on the page that matched your search query. This is handy for figuring out if the previewed site is actually talking about that you are looking for without going to the page.

This can lead to some interesting results because it highlights areas on the site where it finds the text even if it is behind an image because the designers are using image replacement, or perhaps the text shows up in a rotating banner, but doesn't come up in the screenshot.

For example do a search on "Dedicated Servers" and look at the preview for Hivelocity.net. You will see Google highlighted the middle of an image, but this is where they find the text in the site.