Get ready for Yammer, Microsoft announced today – and it’s not...

Get ready for Yammer, Microsoft announced today – and it’s not kidding. Microsoft said this afternoon it will begin to activate Yammer for all its eligible Office 365 business customers starting today, in what’s a major push for the enterprise social networking service. The rollout will come in waves, beginning with those customers who have a business subscription, and fewer than 150 licenses, including one for Yammer.
The second phase of the rollout on March 1st will expand Yammer to larger business customers, who have fewer than 5,000 licenses, but excluding those with education subscription.
The final phase, or Wave 3, starts on April 1, and will include those education subscriptions, as well as all remaining customers.
The end result of this push is that every Office 365 users with a Yammer license will be able to use the service from the Office 365 app launcher, as well as start Yammer conversations from within SharePoint, Office 365 Video Portal, and soon, Delve and Skype Broadcast as well.

https://techcrunch.com/2016/02/02/microsoft-turns-on-yammer-for-office-365-business-customers/