I'm not going to plug our product's features here, but I'll say this: microblogging is not an accurate portrayal of what it is anymore, and hasn't been for at least one and a half years.
Care to elaborate on what it is? At work we looked at Yammer, some people use it and others don't. However, my impression awhile back was "great another facebook but for work". (I mean no offense to it, I am honestly interested in how you view yammer.)