Google has always been concerned about security, so it's no surprise it has taken this step over Symantec's decision.

According to Symantec it doesn't believe its customers of secure sites will be impacted by this removal. If you have a certificate with Symantec you should be looking into this.

Time will tell on this one.

Over the course of the coming weeks, Google will be moving to distrust the “Class 3 Public Primary CA” root certificate operated by Symantec Corporation, across Chrome, Android, and Google products. We are taking this action in response to a notification by Symantec Corporation that, as of December 1, 2015, Symantec has decided that this root will no longer comply with the CA/Browser Forum’s Baseline Requirements. As these requirements reflect industry best practice and are the foundation for publicly trusted certificates, the failure to comply with these represents an unacceptable risk to users of Google products.
Google Takes Steps Over Digital Certificate Security [googleonlinesecurity.blogspot.com]

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