One of big things I see with Office 365 is the integration with social. I have been a big fan of Yammer and have been using the free offering for a while now.
Recently I started to configure the direct integration with Office 365 so I could take advantage of all the new things that are coming such as Officegraph and project Oslo.
However, the main reason I wanted Yammer integration was based n this post:
Yammer bring conversations to your OneDrive and SharePoint Online files
That highlight how Yammer can work with SharePoint today.
As you can see from the above, after configuring my Yammer network and then turning it on as my default social network I have the conversations feature available to me. Yeah-HA!
Now it’s ‘play’ time.