Google has confirmed with us that on Thursday, September 27th, they
released a Panda algorithm update – this would be the 20th Panda update
and thus we are naming it Panda 20. This is a fairly major Panda update
that impacts 2.4% of English search queries and is still rolling out.
Late Friday
This is actually a Panda algorithm update, not just a data update. A lot
of the most-visible differences went live Thursday 9/27, but the full
rollout is baking into our index and that process will continue for
another 3-4 days or so. This update affects about 2.4% of English
queries to a degree that a regular user might notice, with a smaller
impact in other languages (0.5% in French and Spanish, for example).