AlyssaS - 4:12 am on Jul 15, 2011 (gmt 0)

walkman and indyrank - click on one of those subdomains. Look at the homepages, and look at the category pages.

Then compare to a blogspot.

With hubpages - the structure with the duplicate versions of the category pages (hot, latest and best) on the primary domain, the links between the hubs back to the category pages on the primary domain and vise versa, the links between the good authors and the bad through fanning, the aggresive overlinking through the hubtivity, the amount of links on the subdomain home page - all are elements that I think hurt hubpages. And they've been retained in this new re-incarnation.

We know link structure is an issue from Matt Cutts in his last livechat.

[searchengineland.com...]

They haven't really resolved link structure, apart from moving parts of the site onto subdomains.


I guess at the end of the day it all depends on the relationship between domains and sub-domains.

My understanding is that a bad subdomain doesn't usually affect a good primary domain, but a bad primary domain can infect all the subdomains.

So with blogger (and wordpress.com, typepad.com and others), the primary domain is clean and pristine. Some of the subdomains are bad, but they are discrete and therefore don't affect the primary domain (plus they work to get take down the spammy stuff).

Think of the nightmare for G if a single bad subdomain tanked the entire wordpress.com site. So they must have something built into the algo determining the relationship between subdomains and domains - and they probably use interlinking to determine the relationship - and look how they are treating their own blogspot structure - the subdomains link back once to the domain within an iframe in the nav bar at the top, and the domain does not any pass link juice to the subdomains. That's no relationship at all!

With hubpages, for the reasons detailed above, the primary domain has gone bad, and it's key elements haven't changed, and the subdomains are heavily linked back to the primary domain and vice versa.

I think they'll rank well initially, but when the algo catches up with them, it will conclude that they are not discrete elements but part of a single site, because of the heavy interlinking. If I'm wrong, mea culpa.

If there are others with more experience of the relationship between primary domains and subdomains, please chip in!