Robert_Charlton - 12:55 am on Jan 9, 2012 (gmt 0)

...a third essential leg of the ranking algorithm (relevance+connectedness+quality)...

Excellent description. What I've been wondering as I've watched these changes and followed comments on them is whether all factors of the "quality" component, which we call Panda, are being revised with each iteration.

It may well be that they are not... ie, that Google is isolating some factors within "quality" and testing them separately, to keep a better handle on the changes.