I thought for sure they were still treating them as their own domain entities still, but I keep reading that they were switching over to treating them as folders: Dec 7, 2007 http://searchengineland.com/sub-domains-to-be-treated-as-folders-by-google-12865.php "Matt Cutts of Google said at PubCon that Google will be treating sub domains similar to how they treat folders on a site."
They stopped treat a sub domains as a domain for a while now, long ago. The reason why they do that is because people started to use sub-domains for all pages they have on their site, which helps in SERP
Then what about blogger and .wordpress, do they still do the same with them? Does it mean that sub-domains wont rank in serps?
Couldn't have been that long ago since Matt made it public that they WOULD START doing it a year ago.
Just watched the interview I think its just a tweak to make it harder for people to rank for the same keyword more than once under the same domain. Its just a tweak- it will not affect wordpress, blogger, and all that stuff. From my understanding- its just for the same keyword, not subdomains as a whole. Plus he stated that they already implemented it and .wordpresses show up along with other subdomains Thanks Mike
i suppose it depends what you mean by "treating as" really? how they pass PR to each other? how they interact with (or not) with each other in the SERP. still different on one, both counts from what I see.
Doesn't PR just apply to pages and not whole sites - whether or not they are subdomains? I often get two pages on my sites ranking well for a particular keyword. Doesn't each page get treated independently - assessed for content, links and so on?
Google treats internal links differently from external links. Previously Google was treating sub domains as external links, but last year they said they would be switching to treating them more like internal folders.
I've actually learned first hand that Google started treating subdomains as directories (happened months ago). I had some websites on subdomains where the main domain had 0 links. The websites were doing well until one day when they fell drastically. I then started to build links to the main domain and within 2 months the subdomains were also stronger than ever. The stronger the domain is - the stronger the subdomain is.
The Google change only affected the cheaters! If you have a site on a sub domain, it follows the same rules that all sites and pages have.... If you have a particular page that has foul content, too many outgoing links, etc. etc. it will not get PR no matter what type of domain or folder it is in. I have many sites that are in sub domains and they do just fine.
Are the site's main domains optimized as well? If so they'll do fine. But imagine purchasing domain.com and optimizing only sub.domain.com - probably won't work as well as if you optimize both.