Strange behavior of Google

Many sites dropped immediately to low positions....

[lolo7]

Hello All,
I've read for a long time but write for the first time.

The situation is - I have about 40 sites. All of them is subdomains of one domain. All 40 sites have PR=7 and about 1000-1500 inbound links with appropriate texts.
Several are listed in DMOZ and Yahoo.
For about 1,5 years all of the sites stayed in top-5 for their queries (about 100 queries). Dances went, but sites continued to remain on the first places - all was OK.
Suddenly, at last friday I noticed that all sites for all queries loses their positions - from first page they've fallen to 2nd, 3d and 4th pages. All as one! For all queries (about 100).
I thought that this is EverFlux and started to wait the Dance.
So the Dance is in progress but nothing has changed, moreover the situation now is more badly then earlier.
At the same time no significant parameters (number of links to pages (in www2 and www3 the number of links has increases), Page Rank, site's content, mention numbers in Google (ODP), Yahoo) have changed. The PR is still 7 for all ~40 sites.
And another strange fact - there are so many poor and irrelevant sites above me now. Some of them have PR =2 or even 1, they has irrelevant texts but stay above. Moreover when I search the query that exactly the same as a title of some page I find many irrelevant pages with small PR's that do not contain such title and in deeper hole there is my page with that title and PR=7...
I know that the Dance is still dancing but I've not seen any positive changes for about 2 days.
What does it mean?
I've got a strange penalty? Or this is the bug in GG?

Who can explain me?

[djgreg]

Could you imagine a reason for a penalty? Seems really strange to me, but maybe you wait until the dance is over.
Maybe it is because of the Subdomains? 40 Subdomains are a bit much in my opinion? But i don't know at all.

[lolo7]

digreg, thank you for reply.
A reason for a penalty? May be it's because of subdomains. But for about 1.5 years there have been all good. We use subdomains because our main site is fully dynamic, we use sessions etc and we developed the static subdomains for SE. But there are no any hidden texts, hidden links, cloacking and other spamdexing on them. And several subdomains were successfully submitted to ODP and Yahoo. And the main thing - PR's and inbound links don't changed. They only increases now.

[Dante_Maure]

Keep in mind that Google has gotten much better at indexing dynamic pages over the last few months.

You might want to check your logs to see if the Googlebot has been digging deeper into your root domain's dynamic content than it used to.

If so, you may be receiving a penalty for duplicate content.

[ndaru]

lolo7,

I have just the same situation on my site and it has PR6. It has dissapeared from the search result, even using its own name.

As for the possibility of penalty, hmmm... just imagine that webmasters are being punished for doing something that they think is normal and non-cheating.

[djgreg]

The longer I think about that I more and more feel that it isn't a penalty. If somebody is hit by a penalty always the PR goes down. In your two cases the PR was stable.
Are the backlinks shown when you type link:www.mydomain.com?
If they are shown you can be sure it is not a penalty.
Maybe something in the Algo was changed which disadvantages Subdomains, but I have a new Subdomain with 3 major keywords and it made NR1 on all keywords ;) Competitors will get biiig eyes.

[lolo7]

djgreg,
The backlinks are shown when I type link:www.mydomain.com.
More than 1000 links for each subdomain.
In www3 and www2 I see more links than in www.
Maybe something in the Algo was changed but I don't believe in it. Because in all themes (I am a SEO-guy and working in several themes now) there are no strange things - all is fine.
And such strange things that I described above (irrelevant sites with smallest PR above my old pages with high PR) makes me crazy, and I think that this is the some kind of penalty. Maybe for duplicate content (the content in subdomains and in deep pages of "main" dynamic domain are the same), but for 1,5 years I've stayed in top-5 without any problems.