It may happen because after any update it is released in two or three days. So you just have to wait for some days or search in any SEO related news sites.
I think, there are no updates from Google either Panda or Penguin, best way to stay updated with any updates is to Subscribe to SEO related blogs or Subscribe on SEOMOZ, or Search Engine Watch.
Google launched the Penguin Update in April 2012 to better catch sites deemed to be spamming its search results, in particular those doing so by buying links or obtaining them through link networks designed primarily to boost Google rankings. When a new Penguin Update is released, sites that have taken action to remove bad links (such as through the Google disavow links tool or to remove spam may regain rankings.
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