Could anyone please tell me about the latest Google update that is Google Penguin update?
Google Penguin update is all about link farm and duplicate content. You can read here more about this; http://searchenginewatch.com/article/2172839/Google-Penguin-Update-Impact-of-Anchor-Text-Diversity-Link-Relevancy
Yes, this update for those sites have duplicate, overlapping, or redundant articles on the same or similar topics with slightly different keyword variations
This update is all about spamming and duplicate contents of same keyword which is forcefully stuffed in any website or article.
I just found the 50+ updates with Google search for April. For your reference:
Google penguin is latest update and this was about spamming and duplicate content that you used on your website. Many of people lost their ranking after this update.
Penguin was an update to the Google algorithm that was released on the 24th of April, with intention of apparently penalizing sites for over-optimization, otherwise known as spamming.