There is lots of website who update related content on daily basis. i.e seomoz , searchenginewatch , searchenginejournal etc.
When your site is heavily affected then you can understand that it is due to any update in Google, my site went from third position to far away when penguin was updated.
Build your website or blog with your visitors in your mind and google penguin won't affect you any time.
Well just remember that penguin is for spam and bad quality links and panda in all about copy pasting.
Subscribes on Google Alert and select Panda and Penguin Topic, it will give your alert and latest news on selected topic on your subscribed email id daily basis, url:http://www.google.com/alerts . Subscribe Google Official blog for webmaster it is http://googlewebmastercentral.blogspot.in/. Follow Google's official account on twitter for every updates from Google, https://twitter.com/google On other hand signup Google webmaster tool
Googles Official blog usually tell when they updates penguin or panda. Url is http://googlewebmastercentral.blogspot.se/
U can't see the latest update of Google Penguin and Panda but u can read about these update from various sources.