We use Yammer at our 300-person company and we've found it really valuable. We're roughly evenly distributed in 4 countries, so having somewhere which is asynch

We use Yammer at our 300-person company and we've found it really valuable. We're roughly evenly distributed in 4 countries, so having somewhere which is asynchronous where people can see what's happening around the group provides a sense of connection between our staff. Anecdotaly, I've found it particularly valuable amongst IT people who feel more comfortable sharing ideas and opinions on there than they might do in person.