I guess Yammer is positioned more of a communications tools (blogging/tweeting/messaging) whereas Asana is more of a productivity tool (issue tracking/todos/pro

I guess Yammer is positioned more of a communications tools (blogging/tweeting/messaging) whereas Asana is more of a productivity tool (issue tracking/todos/projects)? My point is that trying to spread an app aimed at enterprises using a large-scale bottom-up approach seems to be a relatively unexplored approach. I don't know how Yammer is doing, but I have never seen one of my business partners or co-workers use Yammer and thus be exposed to it (=bottom-up).