I would be interested to hear of someone who has 'ethically' done this.

Because when I when first read this, I actually had the same question:
"Why in the first place would you have 20 domains?"

Google used to give preferential treatment to exact match domains, so many people launched multiple sites for the different section of their sites instead of launching a massive website with many subdirectories. Also think about people that launched separate websites for each of their office locations (exampleNYC.com, exampleLondon.com, exampleChicago.com). I can think of many legitimate cases this applies to.

You would have 20 domains because you got tired of working on one only to see it kicked to page 5 with every new Google update. "maybe there is something wrong with this site?" hmmm, ok, frustrated I think I'll start a new site and work on that for a change.

As for the video - I have a pair of seasonal sites and within 3 days of interlinking them I lost significant traffic(4 years ago) that has never returned. It made sense to interlink them, it was ethical, but that didn't matter.

As for the video - I found it interesting that Matt was comfortable at about 10 interlinked domains in the footer but got iffy at 20. This, to me, suggests some interlinking even from the footer will not cause an instant penalty per say(but may have, 4 years ago).

"Why in the first place would you have 20 domains?"

I have lots more than 20 domains. My sites tend to have similar themes but concentrate on individual states. So while the overall theme may be the same, the content is specific to its location. There are multiple types of themes. There are 50 states. QED.

"Why in the first place would you have 20 domains?"

Site's I watch require a multi-national brand presence, with different localised content surfaced to appear in the SERP's.

None of the interlinks are manipulative, that is, they don't contain varied anchor text on different pages. This tactic used to be around for ranking 5-6 years ago, not sure how it's doing now - but personally I don't want to know about it.

Cross linking is one thing, but supporting multi domains in Google's current environment is anything but smooth, and most folks I know with large resources dinged the strategy long ago, preferring IP based content alterations where practical on a single domain and/or folder structure. The architecture used is beyond me and requires meticulous design by skilled folks (many might frequent these discussions ). And of course, this is not always practical either.

With that type of awareness [ and other things ] , MC might well question why folks would want 100's of domains interlinking - but there may well be practical applications he's not aware of. I wouldn't worry about the magic 10,or 20, it was likely a throw-away line.

Just don't confuse Google's algorithms - keep it simple and practical IMO

I would be interested to hear of someone who has 'ethically' done this.

CNET? The owners of this site?

At one time I had about 10 sites about 7 years ago, I decided to follow google suggestions and combined them into 2 large sites. The original 10sites all ranked well and after I combined them
they ranked even better. The last penguin update the 2 sites got hit, so I uncombined them back to 10 sites and the 8 sites when back to ranking well and the 2 main domains just came back to their old rank before the update.

It seems google like shallow light content sites.

I am back to my old ways thanks to google. I will now create another 10 sites. Google is broken.

@ Garya:

So both the sites that you mentioned in this thread:

The Tale of two websites hit by Penguin 2.0
[webmasterworld.com...]

Have now regained the rankings they lost when Penguin 2.0 struck?

Yes both sites are back to normal slightly lower then before, but I can't complain, plus I have other smaller sites that are ranking well.

@ Garya

I would be careful making that statement or more accurate I would be careful making business decisions on your assumption. Correlation is not the same as causation.

Just stating what i see, direct and to the point, others can come to their own conclusions.

I have been doing SEO since 1999

I would be interested to hear of someone who has 'ethically' done this.

Same reason as netmeg except uk regional sites. It must be ethical as Google accepted different adword campaigns for each site. Unless adwords is out of sinc with Google Spam.

I was disappointed with the video it offered no distinct answers and was very unclear.

it offered no distinct answers and was very unclear

@seoskunk - What answers was it lacking and what was it unclear on for you?

I would be interested to hear of someone who has 'ethically' done this.

Same reason as netmeg except uk regional sites.

I am not sure netmeg was stating that she cross links her sites (maybe she does, maybe she doesn't). I think her response was to the question of "why have 20 domains (instead of one big one)"

I only bring this up because netmeg is pretty much about the most ethical SEO person I know, and someone might misconstrue this as implying that netmeg is unethical.

Thank you for that, sure I'm ethical (and careful) with my own sites and those of clients, but remember, if you don't experiment with things you don't learn, what what?

And yes, many (but not all) of my sites are interlinked. We don't put up 40ft fences along the borders of states (yet) so someone in Michigan could well be interested in something in Indiana - in fact, there's a word for it - Michiana.

@ Whitey

I don't think he answered the question at all, he just waffled on about a hypothetical case on country wide domains but didn't specifically answer if it was a spam thing to do, also neglected regional domains.