Microsoft details its roadmap and pricing for SharePoint-Yammer integration | ZDNet

Microsoft will be offering the following Yammer/SharePoint products and services at these price points:
Yammer Basic Standalone: Free
Yammer Enterprise Standalone: $3 per user/per month
SharePoint Online (Plan 1) + Yammer Enterprise: $4 per user/per month
SharePoint Online (Plan 2) + Yammer Enterprise: $8 per user/per month
Office 365 E Plans 1-4 + Yammer Enterprise: $8 - $24 per user/per month
(All these Plans 1-4 referencesare part of Microsoft's Office 365 plans/pricing, for those wondering about the nomenclature.)

Here's what we know now about the updated Yammer integration roadmap:

• The ability to replace the SharePoint/Office 365 newsfeed with Yammer is coming this summer. According to Microsoft, some customers have been unsure as to whether they should use Yammer or SharePoint for their news feed. As of today, Microsoft's answer is "go Yammer" if possible, whether using Office 365 and/or SharePoint Online in the cloud or SharePoint on-premises.
• Microsoft will provide guidance on how to replace the SharePoint newsfeed with the Yammer newsfeed in SharePoint Server on-premises this summer.
• Single sign-on is coming this fall as part of an Office 365 update.
• The user experiences of Office 365 and Yammer start to converge this fall. (A fairly blurry mock-up of what this means is embedded in this post above.) This is also when the new Yammer experience will add "rich document capabilities" and integration of the Office Web Apps' editing/coediting of Word, PowerPoint and Excel documents

As of 2014, Microsoft is going to be updating Office 365 with "new social enhancements" every 90 days. Office 365 already is on a quarterly (or more frequent) update schedule. These social enhancements will include integration between social and collaboration/email/IM/voice/video and line-of-business apps
ZDNet