The biggest benefit I've seen out of Yammer is in the fact that it increased employee interaction, not just document sharing. After my company rolled it out, I

The biggest benefit I've seen out of Yammer is in the fact that it increased employee interaction, not just document sharing. After my company rolled it out, I was shocked at how many of us took to it. Everyone knows the reason: it looks and feels like Facebook. When we encounter that look and feel, our minds go into "sharing" mode. We get comfortable because it feels like a comfort zone. We share documents, but we also joke around more. Our interpersonal relationships got better, and I'm sure that had a positive impact on our work. I don't think Google+ will have an equivalent effect because few people visit it habitually, and when they do, most posts are fairly formal/professional instead of playful/casual. Despite Google+'s intentions, it doesn't encourage a relaxed mindset.