is Yammer being decommissioned

[null null]

Is there a plan to decommission the Yammer in Office 365. 

[#2]

No, in fact Yammer is being integrated more closely with SharePoint and Teams

See Microsoft 365 Roadmap here

https://www.microsoft.com/en-us/microsoft-365/roadmap?filters=&searchterms=Yammer

It is very much still part of the service.

Hope that answers your question.

Best, Chris

[#3]

No

https://techcommunity.microsoft.com/t5/Yammer/Yammer-may-be-dead/td-p/54613

https://www.quora.com/Is-Yammer-dead

https://techcrunch.com/2018/04/08/in-a-slack-world-microsoft-bets-on-teams-and-yammer/

[#4]

No, not in the slightest! While it might not get as much attention as some other services in Office 365, Yammer provides essential functionality and has its place, alongside everything else. Have a browse through some of the resources here and I think you'll understand better how relevant Yammer is:

https://resources.techcommunity.microsoft.com/resources/yammer-adoption/

Also, make sure to check out the blog, which has plenty of updates.