Just saw this:
Googlite explains PageRank tweak | The Register

Anyway, my sites have all been affected and effected (please forgive my word-play)

EFFECTED:

• My PR6 sites all went down to PR5
  • Sub-pages to PR4/PR5
• My PR4 went down to PR3

AFFECTED:

• My PR0 went up to PR3
  • Site is 2 months old
• My PR0 went up to PR4
  • Site is 3 months old
• PRGrey to PR0
  • Site is 6 months old

Here is a thought:

One of my PR6 sites is now PR5, and every sub-page is PR4/PR5 - excluding a sub-page
that had no crazy content or sold links (nuthin' like that ) - but it did have a
banner ad for TLA (Text Link Ads). And again, I've not sold links on it, but just that one
page had that ad. The content is relevant to the rest of the site - but only that page is a PRGrey...

Edited to say that this is my experience, and in no way am I saying that if you run TLA ads,
you will definately loose your PR ranking. It's just what I have seen on one of my sites,
and could very well be due to some other influence - just added for Food For Thought...

YMMV

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